UNIVERSITY OF CALIFORNIA PUBLICATIONS COLLEGE OF AGRICULTURE AGRICULTURAL EXPERIMENT STATION BERKELEY, CALIFORNIA CALIFORNIA WHITE WHEATS BY G. W. SHAW and A. J. GAUMNITZ BULLETIN No. 212 April, 1911 8 A C R A M K N T W. W. SHANNON - SUPERINTENDENT STATE PFJNTrNi. 1911 EXPERIMENT STATION STAFF. E. J. Wickson, M.A., Director and Horticulturist. E. W. Hilgard, Ph.D., LL.D., Chemist (Emeritus). W. A. Setchell, Ph.D., Botanist. Leroy Anderson, Ph.D., Dairy Industry and Superintendent University Farm Schools. M. E. Jaffa, M.S., Nutrition Expert, in charge of the Poultry Station. R. H. Loughridge, Ph.D., Soil Chemist and Physicist (Emeritus). C. W. Woodworth, M.S., Entomologist. Ralph E. Smith, B.S., Plant Pathologist and Superintendent of Southern California Pathological Laboratory and Experiment Station. G. W. Shaw, M.A.> Ph.D., Experimental Agronomist and Agricultural Technologist, in charge of Cereal Stations. E. W. Major, B.Agr., Animal Industry, Farm Manager, University Farm, Davis. F. T. Bioletti, M.S., Viticulturist. B. A. Etcheverry, B.S., Irrigation Expert. George E. Colby, M.S., Chemist (Fruits, Waters, and Insecticides), in charge of Chemical Laboratory. H. J. Quayle, A.B., Assistant Entomologist, Plant Disease Laboratory, Whittier. W. T. Clarke, B.S., Assistant Horticulturist and Superintendent of University Exten- sion in Agriculture. H. M. Hall, Ph.D., Assistant Botanist. C. M. Haring, D.V.M., Assistant Veterinarian and Bacteriologist. John S. Burd, B.S., Chemist, in charge of Fertilizer Control. E. B. Babcock, B.S., Assistant Agricultural Education. W. B. Herms, M.A., Assistant Entomologist. J. H. Norton, M.S., Assistant Chemist, in charge of Citrus Experiment Station, River- side. W. T. Horne, B.S., Assistant Plant Pathologist. J. E. Coit, Ph.D., Assistant Pomologist, Plant Disease Laboratory, Whittier. C. B. Lipman, Ph.D., Soil Chemist and Bacteriologist. R. E. Mansell, Assistant in Horticulture, in charge of Central Station grounds. A. J. Gaumnitz, M.S., Assistant in Cereal Investigations, University Farm, Davis. E. H. Hagemann, Assistant in Dairying, Davis. B. S. Brown, B.S.A., Assistant in Horticulture, University Farm, Davis. F. D. Hawk, B.S.A., Assistant in Animal Industry. J. I. Thompson, B.S., Assistant in Animal Industry, Davis. R. M. Roberts, B.S.A., University Farm Manager, University Farm, Davis. J. C. Bridwell, B.S., Assistant Entomologist. C. H. McCharles, B.S., Assistant in Agricultural Chemical Laboratory. N. D. Ingham, B.S., Assistant in Sylviculture, Santa Monica. E. H. Smith, M.S., Assistant Plant Pathologist. T. F. Hunt, B.S., Assistant Plant Pathologist. C. O. Smith, M.S., Assistant Plant Pathologist, Plant Disease Laboratory, Whittier. F. L. Yeaw, B.S., Assistant Plant Pathologist, Vacaville. F. E. Johnson, B.L., M.S., Assistant in Soil Laboratory. Charles Fuchs, Curator Entomological Museum. P. L. Hibbard, B.S., Assistant Fertilizer Control Laboratory. L. M. Davis, B.S., Assistant in Dairy Husbandry, University Farm, Davis. L. Bonnet, Assistant in Viticulture. S. S. Rogers, B.S., Assistant Plant Pathologist, Plant Disease Laboratory, Whittier. B. A. Madson, B.S.A., Assistant in Cereal Laboratory. Walter E. Packard, M.S., Field Assistant Imperial Valley Investigation, El Centre M. E. Stover, B.S., Assistant in Agricultural Chemical Laboratory. P. L. McCreary, B.S., Laboratory Assistant in Fertilizer Control. F. C. H. Flossfeder, Field Assistant in Viticulture, Davis. E. E. Thomas, B.S., Assistant Chemist, Plant Disease Laboratory, Whittier. Anna Hamilton, Assistant in Entomology. Mrs. D. L. Bunnell, Secretary to Director. W. H. Volck, Field Assistant in Entomology, Watsonville. E. L. Morris, B.S., Field Assistant in Entomology, San Jose. J. S. Hunter, Field Assistant in Entomology, San Mateo. J. C. Roper, Patron University Forestry Station, Chico. J. T. Bearss, Foreman Kearney Park Station, Fresno. E. C. Miller, Foreman Forestry Station, Chico. CALIFORNIA WHITE WHEATS. KINDS OF WHEAT. Note. — The major part of this bulletin is the result of work done by Mr. A. J. Gaumnitz as a candidate for the degree of M.S. To the data so secured has been added other data which seemed to be closely related. Credit should particularly be given to Messrs. B. R. Jacobs, and E. J. Lea, for portions of the routine chemical work, and to Miss Edith Miller for the microscopic measurements. At present agriculturists quite generally recognize eight species of the genus Triticum, as follows : Triticum vulgare, Triticum compactum, Triticum turgidum, Triticum durum, Triticum polonicum, Triticum spelta, Triticum dicoccum, and Triticum monococcum. The last three species named are of little value in this country directly, and become important only in so far as they are used in improving the commonly produced varieties by methods of breeding. Emmer and speltz are grown in considerable quantities in Russia, Germany, France, Spain, Italy and Servia, and the monococcum (einkorn or engrain) in the same countries, but to a lesser extent. Speltz is used mainly as cattle food. Emmer and monococcum are used as a human food to a limited extent. Though the botanic characteristics of the Poulard, Polish and Durum types are quite distinct in kernels and other parts, their adaptation and uses are very similar. They are quite rank, hardy growers, and suited to the semi-arid regions. The Durums are well adapted for the produc- tion of macaroni. Durum flour when blended with that of the common bread wheats, produces a bread which compares not at all unfavorably with that from ordinary flours. These wheats possibly may be used for blending to improve the common wheats, and especially California white wheats, for they are relatively high in gluten. From a field standpoint they are fairly rust resistant, are able to subsist on a minimum of moisture and at the same time withstand quite high temperatures. The common bread wheats (Tr. vulgare) are a quite variable species and are the most extensively grown of any in the United States. They have been known especially for their bread-flour producing qualities, but setting aside prejudice it is questionable whether they should longer hold that title to the exclusion of the best durum varieties. There is a considerable difference in the bread-making qualities of the different varieties of the common wheats, and when the durum wheats of good 316 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. quality are ground into flour and baked, in comparison with the bread wheats, it is readily seen that in flour-jdelding power, color and lightness of the loaf produced, they compare very favorably. The hard wheat area is being rapidly extended northward into Alberta and adjacent provinces. This class of wheat is what the Minne- apolis mills grind into their world-famed flours. Although some Kan- Bearded type of common wheat. Beardless type of common wheat. A Durum wheat. Fig. 1. — Showing typical wheat heads. One half natural size. sas hard wheat is also used. 1h isl&ilsil^ c S « 3 *-< TZ il o O ft K fl £-*= .2 ° ^^^Hj o 02 Ctf §1 ^H ^B ^J C .M d s r- CO f- ^HT ; ■■ c (B ft Br b1 ■w X H9 ■ -ft ' • ^H c d v a> ^K >•' Hj s ■ss ■n. fl o &2 o ■f B o - £ CO B9 qj CD -t-> S* 3 3 ♦* £ be ■7 ■ s a) ft T3 « 0-i-> Ba. '• n od ft.. ■t -!-> HHHH^^s^Hk Irt •W'O ^BV . • ' ' ^Hl 00 o a> ■ w *"• S-I ft to O© ^#« s o s a cS Bf^H o.£ H^L Hi «o -S:=j Bk^^sI 00 cc= HI c* g HELD CHARACTERISTICS. WHITE AUSTRALIAN. This is a free-stooling, prolific, hardy, late, mid-season wheat. It is quite subject to rust attacks, and has only a me- dium tenacity. It is not well adapted to the coast sections on account of its liability to rust. CHARACTERISTICS OF GROWTH. Stools: Fairly abundant, spreading, rather creeping. Straw: White, strong, sup- ple, rather tall. Foliage : Good color, abund- ant, drooping, slightly glau- cous. Heads: Bald, smooth, long, regular, somewhat open, rather slender, taper- ing. Spikelets: Narrow, two to three grained, not close. Grain: Large, long, plump, white, soft, opaque, starchy interior. The grain is of pleas- ing appearance and generally of good bushel weight. A typical White Australian should grade about as follows (Fig. 4) : Fig. 3. — White Austra- lian wheat. 320 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. HH ^ •- o ^i^L^L^^H^LBh § flJ.fi HV9I ° S £ ^B „^H <3 'O IK-'^H a pj a> l^lm.1^1 o — £ I^^^H^^B *"• ft*"" ^^^^H^^^^H 0«M h^^^^BHh *■ o ^HH 5 be ^^^^^^^^^H d H^^^^H^^^H d C • ^^H^^^H^^B £ ^^H^^^B r, EC a> ^H .C |^^H *S K&B p2 3 "f . A O ^m . ^H g O^ 41 iY '. -• " * ^^H ° ; H u - d & I 24.2 p izes i rate ■IIei ^H IgHk^^D to d iCGEflK^flSiil ft TO

-0 9 <*-> TO ■HBB^Kie O P V V ^ TO C C C 4) ^p^.'H S •- a> « d $h h b o Hp^f&fl » bC TO L^Lk^^^I o «,_, *J Hi^i^i^^BBl^l ft 4 I^BHH •1 HHjHK d £ «KHH R'i fl^^l C b£ r- Bv mB 8 CTO r o K 1 a g£ii n ^B • ~ «M 'q. Hh^hI KB&jgljjB o-g HHGBbvJS! TO o J^HkhSk d ^^^^^^^^™ £ LITTLE (SALT LAKE) CLUB. This is a strong-growing, medium- stooling, hardy, mid-season wheat. It is very subject to rust attack. The chaff has a very high tenacity, this being one of the particular points in its favor in the interior valleys where the winds are strong. It ripens a little earlier than White Australian and is somewhat more prolific. CHARACTERISTICS OF GROWTH. Stools: Few and erect, strong- growing. Straw: White, strong and of medium height. Foliage: Good color, fairly abundant, upright and smooth. Heads: Awnless, smooth, short, flat, compact; chaff yellow and tenacity high. Spikelets: Wide, 2-5 grained, close. Grain : Medium large, short, white, irregular in shape, very soft and starchy interior. The grain has a flat side which makes it apparently larger than is really the case. A good type of the Little Club should have about the following grade (Fig. 6) based upon the method of grading by sieves as set forth in Bulletin 181 of this station. Bulletin 212] CALIFORNIA WHITE WHEATS. 321 SONORA. This is a light-stooling, rapid-growing, early wheat. It is much subject to rust, hence only adapted to the interior valleys. Its leaves are narrow and thin, and well adapted to withstand considerable drought. For this reason it has been the variety which has held its own in those portions of Fig. 7.— Sonora wheat, the State UlOSt Subject to One half size. -. v, i .-, drought, namely m the southern portion of the San Joaquin Valle}. CHARACTERISTICS OF GROWTH. Stools : Few and erect with medium growth. Foliage : Light color, not abundant, texture thin, surface rough. Heads: Long, medium thick, somewhat flat, compact, hairy and awnless. Spikelets : Three-grained. Grain : Short, round, plump, white, starchy interior. It is of unusually pleasing appearance and of good bushel weight. The grading of a good sample of Sonora showed as follows (Fig. 8) : T'Cii $v W O O c "3, a -i; o o 8 Q 2 '"'. c o £3 v bfl G £ ° p Z tc a ~ o i — A w Ph co ^ w CD ■S . *-■ § rt X - G o ® A Q O 5 a> 3 rt bo c O «S CO £ 5 ° O CO > O co O) co "3 CO 322 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. Fig. 9. — Propo wheat. One half size. PROPO. This is a fair-stooling, medium early, vigorous growing, bearded variety. Its yielding capacity is unusually good where winds are not too severe. The texture of the leaf is rather thin, thus enabling it to withstand rather severe drought. CHARACTERISTICS OF GROWTH. Stools: Fairly abundant, slightly spreading. Straw: Purplish white, medium strong, good height. Foliage: Dark green, drooping, only fairly abundant, slightly rough. Heads : Bearded, smooth, long, open, medium slender, tapering. Spikelets : Medium wide, open, three grained. The relative percentage distribution of these several sorts of wheat in the State is shown in the following table, taking the points named as centers, the figures given being the results of estimates of a large num- ber of buyers in the several regions. TABLE L— SHOWING COMPARATIVE DISTRIBUTION OF VARIETIES OF WHITE WHEAT IN CALIFORNIA. Tributary to (0 I White Australian w n f 3 a o | 1 3 o o Visalia 5 5 30 50 90 20 85 30 30 70 60 50 20 30 5 15 50 10 10 40 15 10 10 20 10 5 10 5 10 30 60 50 2 10 10 5 5 3 85 40 Fresno Madera Modesto Stockton Sacramento Woodland Marysville Chico _ Salinas Paso Robles Bulletin 212] CALIFORNIA WHITE WHEATS. 323 These estimates show that the Little Club is the favorite variety in the northern portion of the Sacramento Valley, that it declines rapidly in popularity as one goes southward and can hardly be called popular south of the country tributary to Stockton. In the coast section it is not grown at all. White Australian seems to have a more widely dis- tributed popularity than any of the other sorts. It has its widest use in the middle San Joaquin section and the uplands of the coast region. Washington Bluestem has come into wide favor during the last few years in the middle San Joaquin section and its use is extending north- ward in the Sacramento section. This wheat has all the characteristics of the White Australian, and it is very questionable as to its being at all different. White Chili can be said to be popular only in the section about Marys- ville, although it has a scattered use extending even as far south as Fresno. Sonora is in wide use only in the southern portion of the San Joaquin Valley, where its marked drought- resistant qualities have doubtless made it a "survival of the fittest." Propo, although widely grown some twenty-five years ago in the Sacramento Valley, has been super- seded entirely by other wheat. It is grown to a con- siderable extent now only in the coast section, espe- cially about Paso Kobles. This wheat was, and still is, held in high esteem by the milling trade. FlG ' oL Sf^teT"' IMPURITIES. Before conducting the following tests the samples selected were sub- jected to cleaning for the removal of the weed seeds present. The nature of foreign seeds found during this work is shown in the following table : 324 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. TABLE II. — SHOWING WEEDS FOUND Number of Sample. 44. 62. 67. 73. 80. 1 81. 204. 1. Agrostemma githago. Corn cockle 2. Amsinckia intermedia. Burweed, fire-weed 3 50 3. Anthemis cotula. Mayweed, dog-fennel 10 4. Avena fatua. Wild oats 1 5. Avena sativa. Cultivated oats 6. Bromus maximus. Broncho grass 59 1 22 12 22 7. Centaurea. Star thistle (small flower) 8. Convolvulus. Bindweed, morning-glory 9. Gilia (tiny seeds) 10. Gnaphalium. Cudweed, everlasting (infinitesimal seed) 11. Hemizonia. Tarweed 9 6 12. Hordeum vulgare. Cultivated barley 33 17 256 204 2 10 13. Leptocaulis (parsley family) 14. Lolium perenne. Rve grass 1 15. Lolium temulentum. Poison darnel ; poison rye grass 17. Phalaris paradoxa. Gnawed canary grass 15 3 25 48 17 18. Medicago denticulator. 2 19. Raphanus sativus. Wild radish 20. Heliotropium currassavicum. Wild heliotrope 20 21. Rumex crispus. Curly dock • 22. Vetch 1 Smut wheat 3 107 3.7 20 19 9 15 301 23 12 241 13 8 75 2.6 20 65 2.2 24. Number of foreign seeds 40 25 Percentage of impurities (foreign seeds) 7.5 The table is of interest particularly in showing, not only the extreme more aspecially because all of these wheats were actually being used by n ling ih«' case, there is abundant reason for the extreme weediness of the of tlx* combined harvester to scatter weed seeds in the fields. Bulletin 21: CALIFORNIA WHITE WHEATS. 325 IN SEED WHEAT SAMPLES. 206. 208. 211. 229. 255. 276. 279. 284. 289. 296. 300. 306. 314. 320. 325. 208. 1 7 2 3 72 13 66 2 36 120 8 150 1 1 8 66 1 5 13 17 3 1 1 1 6 14 1 34 2 1 2 21 50 5 6 2 80 1 2 5 14 3 17 1 4 2 1 13 34 80 30 3 121 6 17 508 56 3 6 18 11 4 122 6 10 2 1 3 1 1 125 26.2 ...... 257 31.0 1 16 2.7 14 39 5.3 2 16 2.0 4 109 10.4 6 2 .15 11 3.1 100 5.8 517 36.7 69 6.2 20 2.7 70 17.7 21 222 1.3 14.0 323 29.4 weediness of the field on which most of these wheats were grown, but farmers for seeding purposes in the condition here represented. This fields in the Ayheat-srrowin^ areas of the State, aside from the tendency 326 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. PHYSICAL CHARACTERISTICS OF WHEAT. The physical character of wheat has been the basis of much study, and certain chemical properties have been shown to be closely associated with well-defined physical characters. The milling qualities of wheats have also been found to be more or less closely associated with certain phys- ical features, especially size of grain, hardness, thickness of bran, and bushel weight. In Bulletin 181 of this station is discussed in detail the matter of size of kernel of a large number of samples of seed wheat collected from farmers. The relative size of kernels of different kinds of wheat is determined by the use of a series of sieves, by weighing a definite and considerable number, or, what amounts to the same thing, counting the number in a certain weight, or by taking the weight per bushel. No one method can be relied upon altogether, because of the variation in the specific gravity ; difference in maturity, causing the grain to be misshapen ; and difference in normal shape of the kernels. In a general way, these dif- ferences are equalized and eliminated, by taking well-matured grain and depending not upon individual determination but upon several deter- minations and averages from these. There is no recognized standard to represent the different sizes of grain, but after considerable study of the range of variation in the grains of wheat, the following meshes have been adopted as suited to the conditions of this study : Size. 12 3 4 5 6 Mesh diam. 3.25 mm. 3.00 mm. 2.75 mm. 2.50 mm. 2.25 mm. 2.00 mm. Fig. 11. — Showing actual size of grain separated by each sieve. The common method of the grading of wheat is by separation of the grains according to size. This is most conveniently done by means of sieves. The grains in a given sample vary in size. If the sample be passed through a sieve having a mesh sufficiently large to retain only the very largest grains, and then successively through sieves with smaller and smaller meshes, until no more grains will pass through, the sample will have been graded, that is, each lot or pile of wheat will con- sist of grains of a definite size. Bulletin 212] CALIFORNIA WHITE WHEATS. 327 The character of the mesh has much to do with a proper grading by this method. The shape of the wheat-grain is such that a slit is required for the openings in the sieves in order to allow the passage of the grain. An examination of the wheat-grains will show that the two transverse diameters are not of the same size, and this must be regarded as hav- ing reference to the shortest diameter in each case. This difference in transverse diameter of grain is easily observed in Fig. 11. The separations were in each case made upon samples consisting of plump grains. The grain represents the crops of three consecutive years extending from 1904 to 1906 inclusive. Fig. 12. -Showing the style of sieve used in the separation of the different sizes of kernels. The several types enumerated above, when separated by means of the sieves here described, gave the following results : TABLE III.— SHOWING MEAN RELATIVE SIZE OF GRAINS OF COMMON CALIFORNIA WHEAT. No. of sample. Size 1. 3.25 mm. Size 2. 3.00 mm. Size 3. 2.75 mm. Size 4. 2.50 mm. Size 5. 2.25 mm. Size 6. 2.00 mm. White Australian Bluestem 43 32 55 11 7 11.62 12.84 14.52 1.84 8.56 10.51 11.63 7.47 2.53 9.05 24.71 25.32 17.13 14.08 17.68 44.69 40.56 47.88 57.10 53.60 7.01 7.17 10.25 20.80 9.96 1.64 2.40 Little Club 2.72 Sonora 3.69 Propo _ 1.19 The above table of grading shows certain characteristics of the grain which will also be observed upon studying the appearance of the grains from the different varieties as shown in the illustrations. In the first place the similarity of the grading of White Australian and Bluestem will be noted, which is in line with the statement made in an earlier paragraph, that these two varieties were very closely related, if they are not even the same variety passing under different names. White Aus- tralian carries 46.8 per cent, of its grains in the first three sizes while 328 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 49.7 of the grains of the Bluestem are carried in the same sizes, and further it will be noted that the distribution in the three sizes is also essentially the same. The Little Club variety is distinctly different from these types and also from those following, the grading giving one the idea that it is a small grain, whereas the appearance to the eye gives one the impression of a relatively large grain. This is doubtless due to the peculiar shape of the Club grain. It has one flat side which makes its transverse diameter really smaller than is apparent. Both the Propo and the Sonora appear from the grading to be small grains. This is actually true of the Sonora, but of the Propo this is only true of its transverse diameter, the grain being rather longer than that of the White Australian. A circumstance shown by this table is the larger weights in per cent, retained on the 3.25 mm. than on the 3 mm. sieve in the first three cases. One would expect to find the relations which are shown by the Sonora and Propo. In an examination of individual determinations a considerable difference is found in favor of the 3.25 mm. sieve. The largest being 24.2 per cent, on the larger sieve to 11.8 per cent, on the next lower size, while below this the percentage increases to the max- imum on the 2.5 mm. sieve. RELATION OF SIZE OF KERNEL TO FLOUR YIELD. This matter of size of grain has an important bearing upon the mill- ing value of a wheat, especially as between samples of the same variety other things being equal. For instance, of two wheats otherwise of equal value for milling, the one whose grains are the larger will give the larger yield of flour. Millers pretty generally recognize this by screen- ing out the smallest grains. This may also be shown by certain results obtained with the mill at this laboratory. Further, we might expect this a priori, because there is bound to be larger percentage of bran upon the smaller grains of the same variety. The following table is intended to show this fact. Here is shown the average grading of a number of samples of grain, each of which has been milled so as to secure the total yield of flour after the same style of milling. For the sake of this comparison, the first three sizes are grouped together and the last three sizes together, and are arranged in order of relative size of grains, the total number of samples used (52) being separated into four groups of thirteen samples each for securing an average : TABLE IV.— SF JO WING THE RELATION OF SIZE OF GRAIN TO YIELD OF FLOUR. Xo of Samples Represented Sizes 1, 2, 3. Sizes 4. 5, 6. Total flour yield. 13 5.3 15.9 28.9 60.7 94.7 84.1 71.0 39.3 691 13 - 69 7 13 . 70.7 1 3 71.4 Bulletin 212] CALIFORNIA WHITE WHEATS. 329 PHYSICAL CHARACTERISTICS. Table V shows certain physical characteristics of the grains. In it is shown the relative size of the kernels as measured by the number in 10 grams, the average weight per kernel, the bushel weight, the hardness when tested under uniform conditions, and the grade as determined by sieves as described heretofore. In Table VI is given a summary of four types, the grouping being in accordance with the number of grains per 10 grams, and subdivided into groups having a range of 50 kernels each. In each case the num- ber of samples falling in each group is given. This is significant in establishing the relation between the four types, as to the relative num- ber of samples from each type falling in the same group, which allows comparisons to be made between the different kinds of wheat of the same size grain. TABLE V.— SHOWING AVERAGE WEIGHT AND HARDNESS OF CALIFORNIA WHITE WHEATS. Blue st em. Xo. of Laboratory kernels number. ' in 10 ! grams. Average weight per kernel. Weight per bushel. Number of unbroken grains under weight of .75 lbs. 1.00 lbs. 1.25 lbs. 1.50 lbs. 1.75 lbs. Total number of unbroken grains.* 64 606 118 17 24 25 152 9 303 121 268 472 15a 10a 16___ 15 4 14 371 299 267 206 205 300 ' 5 386 272 Average ___ 225 231 237 242 242 243 245 257 263 267 268 271 277 277 279 280 285 287 292 298 309 313 313 314 314 334 350 .0444 .0432 .0421 .0413 .0413 .0411 .0408 .0389 .0380 .0374 .0373 .0369 .0361 .0361 .0358 .0357 .0350 .0348 .0342 .0335 .0323 .0319 .0319 .0315 .0315 .0299 .0285 .0363 62. 61. 62.75 61. 59.50 61. 00. 61.12 61. 62. 60.25 i 59. 00. 58.50 60.12 61.25 57. 61. 59.50 59.50 59.75 60.50 60.75 56.25 60.25 58.75 59.50 60.125 100 99 100 100 93 99 94 100 100 100 100 100 100 87 100 100 100 100 99 94 95 95 72 99 100 99 100 97 100 98 100 72 68 54 84 83 100 95 88 99 89 71 43 54 47 87 74 91 74 77 63 91 43 77 86 78 96 94 91 48 41 32 64 48 84 81 54 79 66 56 28 17 20 31 37 65 37 54 51 68 22 43 63 54 82 94 75 17 20 8 40 58 53 16 60 36 30 12 24 12 19 18 12 50 36 59 60 42 5 25 13 2 15 3 11 6 7 22 20 437 445 408 237 222 193 287 231 367 342 260 353 291 247 171 171 167 218 222 285 224 226 212 276 165 231 321 267 •Note. — The figures in this column represent the sum of the figures in the preceding five columns. 2— b212 330 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. TABLE V (CONTINUED).— SHOWING AVERAGE WEIGHT AND HARDNESS OF CALIFORNIA WHITE WHEATS. RELATIVE Australian. Laboratory number. No. of kernels in 10 grams. Average weight per kernel. Weight per bushel. Number of unbroken grains under weight of .75 lbs. 1.50 lbs. Total number of unbroken grains. 452 26 67 73 416 127 605 129 68 66 23 62 453 311 231 304 134 288 232 69 138 184 322 28 275 22 141 326 309 312 78 77 319 310 359 Average ._. 292 216 .0462 237 .0421 240 .0416 249 .0401 255 .0392 256 .0390 256 .0390 259 .0386 260 .0384 261 .0383 264 .0378 267 .0374 268 .0373 268 .0373 272 .0367 274 .0364 280 .0357 281 .0355 288 .0347 293 .0341 298 .0335 298 0.335 299 .0334 300 .0333 302 .0331 306 .0326 316 .0316 326 .0306 330 .0303 330 .0303 337 .0296 342 .0292 369 .0271 375 .0266 443 .0225 .0341 59.5 60.5 62.75 63.12 58.25 61.75 62. 60.50 62.25 61.25 62.25 62.75 60.50 61. 63. 62.50 62. 62.50 59.50 60.25 00. 60.50 60.50 60.25 59. 60.50 00. 61. 59.50 58. 52.50 60. 59.50 57.50 53. 60.29 100 100 100 100 100 100 100 100 100 100 61 100 100 100 100 100 95 100 95 100 92 97 100 100 98 100 95 96 95 100 100 100 100 100 99 97 99 99 98 100 98 91 100 83 100 100 39 81 97 98 90 96 54 96 86 95 50 80 100 99 79 99 50 87 92 99 92 95 84 66 45 86 84 90 88 90 88 37 100 50 90 93 11 47 85 91 23 86 77 61 23 22 93 85 45 85 26 72 80 92 42 58 43 18 29 65 35 61 54 24 50 53 16 28 47 43 9 27 3 10 25 6 25 14 19 12 4 26 395 434 401 375 419 232 443 240 362 396 111 248 410 323 381 327 172 365 289 278 165 199 324 355 241 355 171 293 349 325 240 264 227 184 195 299 Bulletin 212] CALIFORNIA WHITE WHEATS. 331 TABLE V (CONTINUED).— SHOWING AVERAGE WEIGHT AND HARDNESS OP CALIFORNIA WHITE WHEATS. Little Club. Laboratory number. No. of kernels in 10 grams. Average weight per kernel. Weight per bushel. Number of unbroken grains under weight of .75 lbs. 1.00 lbs. 1.25 lbs. 1.50 lbs. 1.75 lbs Total number of unbroken grains. Average 210 226 235 236 243 243 244 247 248 252 255 263 271 274 282 285 286 289 292 306 311 314 315 316 317 317 330 330 332 334 336 337 340 342 355 356 360 363 363 363 363 366 367 373 377 377 390 390 419 537 323 .0476 .0442 .0425 .0425 .0411 .0411 .0409 .0404 .0404 .0392 .0380 .0364 .0354 .0349 .0349 .0342 .0326 .0321 .0315 .0317 .0316 .0316 .0316 .0303 .0303 .0301 .0299 .0297 .0296 .0294 .0292 .0281 .0279 .0277 .0275 .0275 .0275 .0275 .0273 .0272 .0268 .0265 .0265 .0256 .0256 .0238 .0186 59.50 59. 61.50 62.50 62.12 63. 60. 61. 63. 60. 60.75 62. 62. 60. 60.25 63. 00. 62. 61.25 60. 60.75 00. 59. 58.50 58.50 60.75 59. 62. 60. 58.25 61. 00. 59. 60.50 60. 60.25 59. 60.50 60. 58.50 59.50 60.50 57.75 59. 63. 59.50 61.12 59. 59.25 58.87 .0325 : 60.33 100 100 100 100 100 100 100 98 100 100 100 100 98 100 100 100 94 100 100 99 100 95 100 47 47 99 97 100 100 98 100 98 100 100 100 99 94 99 54 23 23 100 100 99 72 78 100 96 95 100 92" 100 97 100 100 99 99 100 94 100 99 100 100 81 100 80 95 83 100 92 66 100 76 84 21 21 76 70 92 63 92 93 68 43 92 96 85 35 88 46 97 60 79 43 66 92 82 37 77 80 100 96 99 98 99 97 100 94 98 94 100 99 55 97 45 89 52 97 67 21 97 34 36 9 9 39 12 57 39 72 58 30 31 64 64 54 27 47 14 63 29 40 24 41 58 41 18 48 60 100 91 95 96 97 95 96 91 85 90 90 91 10 87 10 86 13 96 13 86 6 7 2 20 71 23 2 29 30 25 25 17 8 23 8 10 20 24 13 25 48 100 83 94 90 82 87 86 33 53 62 70 79 59 77 86 44 6 7 7 4 3 5 5 3 3 8 47 500 467 488 484 477 478 482 410 436 445 460 469 244 443 235 447 242 479 272 186 427 211 227 77 77 214 181 275 202 340 281 198 174 289 293 268 181 246 112 23 23 286 189 226 152 205 282 232 150 250 288 332 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. TABLE V (CONTINUED).— SHOWING AVERAGE WEIGHT AND HARDNESS OF CALIFORNIA WHITE WHEATS. Sonora. Laboratory number. No. of , Average j Weight kernels j weight I per in 10 per , bushel, grams. kernel. Number of unbroken grains under weight of .75 lbs. 1.25 lbs. 1.50 1.75 lbs. Total number of unbroken Efains. 167 481 245 74 76 33 63 249 140 137 257 Average 254 .0393 61.50 98 92 272 .0367 66. 100 100 276 .0362 64.75 100 100 296 .0337 65. 100 97 337 .0296 63. 100 100 356 .0280 64.25 100 96 359 .0278 64. 100 93 371 .0269 64.75 96 91 444 .0225 61. 100 70 457 .0218 63.50 97 65 518 .0193 60.25 94 68 358 .0292 63.45 98 88 71 100 93 87 94 87 75 75 29 24 42 35 7 99 80 77. 34 55 25 66 32 73 52 26 9 75 33 4 17 52 34 303 479 404 364 392 408 303 370 203 186 221 330 Propo. Laboratory No. of kernels in 10 grams. Average weight per kernel. Weight per bushel. Numbe • of unbroken grains under weight of Total number of unbroken grains. number. .75 lbs. 1.00 lbs. 1.25 lbs. 1.50 lbs. 1.75 lbs. 46 236 270 322 341 292 .0423 .0370 .0310 .0293 .0349 61. 60.25 63.50 62.75 61.87 100 100 100 100 100 100 76 92- 94 90 89 55 78 52 69 53 40 34 14 35 27 ' 369 45 _ 17 288 47 _ 7 17 311 79 Average ___ 260 307 Bulletin 212] CALIFORNIA WHITE WHEATS. 333 TABLE VI.— SHOWING PHYSICAL CHARACTERISTICS OF WHEATS BY GROUPS. Bluestem. Range of seeds per 10 grams. Number of kernels unbroken under weight of Sieve grading. 200-250— 251-300— 301-350— Average 7 238 13 277 7 321 27 274 61.2 60.0 59.4 60.2 82 66 48 27 318 68.3 78 51 22 5 256 54.4 73 48 16 5 236 35.2 78 55 29 12 270 52.6 31.7 45.6 64.8 47.4 Australian. 200-250— 251-300— 301-350— 351-400— Average 4 234 61.5 100 99 88 71 43 401 65.5 19 274 61.3 97 86 66 36 15 300 50.3 9 321 58.8 98 88 65 28 12 291 31.8 3 396 56.6 100 65 30 6 1 202 10.4 35 306 59.5 99 85 62 35 18 299 39.7 34.5 49.7 68.2 89.6 60.3 Little Club. 200-250— 251-300. __ 301-350— 351-400— Average 9 237 61.3 100 99 98 94 79 470 72.6 10 275 61.3 99 93 80 59 43 374 60.1 15 325 59.8 92 72 41 15 4 224 30.8 14 359 59.8 81 72 41 14 2 210 15.0 48 299 60.5 93 84 65 46 32 319 48.1 27.4 39.9 69.0 85.0 51.9 Sonora. 200-250— 251-300— 301-350. __ 351-400— 401-450— 451-500— Average 275 64.3 100 337 63.0 100 362 64.3 99 444 61.0 100 457 63.5 97 518 60.3 94 323 63.8 100 97 100 93 70 65 68 97 94 79 29 24 42 87 389 393 360 203 186 221 35.7 10.4 12.9 0.0 1.6 2.5 380 19.6 64.3 89.6 87.1 100.O 98.4 97.5 80.4 Grand Average. 200-250 251-300 301-350 351-400 246 314 332 18 399 62.1 61.4 60.4 59.1 99.5 94.2 85.0 70.0 47 395 60.5 ! 98.5 89.2 72.7 45.7 25 306 43.8 96.2 815 58.2 28.5 2 266 27.7 93.6 69.0 33.6 8.0 1 205 8.5 39.5 56.2 72.3 91.5 The discussion of the results appearing in the tables of physical char- acteristics will be based upon the small tables of averages (Table VI) 334 UNIVERSITY OP CALIFORNIA — EXPERIMENT STATION. in order to eliminate the influence of a number of apparently extreme variations which do not seem to be entirely consistent. In the case of Sonora wheat the groups 350-400, 400-450, 450-500 are also eliminated in making up the averages, inasmuch as but a single sample appears in each of these groups, and the previous table shows such a range between different samples that it is thought unsafe to base any statement upon these groups carrying but a single sample. Relative Size of Varieties. — In this table the relative size of the sev- eral varieties is shown in two ways, namely, the average number of grains in 10 grams and the sieve gradings, sizes 1, 2, 3, being the larger- sized grains. Considering the varietal averages as shown in the table, it will be seen that as to size of kernel the varieties stand in the follow- ing order in both instances : Bluestem, Little Club, Australian, Sonora. A constant relation is seen to exist between the size of grain as shown in sieve grading, and the weight per bushel. The table shows in every instance that the weight per bushel increases as the number of grains per 10 grams decreases, that is, as the size of the kernel decreases, the weight per bushel decreases, provided the type of grain remains the same, but if the type changes and the size of grain remains the same the weight per bushel may vary widely. As, for instance, the bushel weight of Bluestem and Little Club in the 251-300 group, with an average number of kernels per 10 grams respectively of 277 and 275, the Bluestem weighed but 60 pounds per bushel, while the Little Club showed 61.3, or a difference of over 2 per cent. It would appear, then, that in the use of this factor in the judging of grains it should be applied only to lots of the same variety. Hardness of Kernels. — It is generally held that the hardness of a grain gives, in a rough way, its general adaptability for milling pur- poses, particularly if the test be applied within the variety. This test is usually given in the purchase of grain by the biting of several kernels, but it is very doubtful if an approximate idea of the relative hardness of kernels of the same variety can thus be established. As between durum varieties and the white wheats it would, of course, be possible to differentiate, and also between the darker-colored wheats of the middle west and white wheats of the west, but as between one lot of Australian and another the matter is very doubtful. Further, it has certainly not been demonstrated that this is a factor of importance. Nevertheless, an attempt was made to make a comparison of these common California sorts, in the matter of hardness, by some method approximating as nearly as possible the biting method, by means of mechanical means of such a nature as to measure the weight used in each case to break the grain, and in this manner establish a means of comparison in this respect. Bulletin 212] CALIFORNIA WHITE WHEATS. 335 The apparatus employed consisted of a pair of ordinary pincers, as shown in the illustration, mounted upon a suitable standard, with a weight attached to the upper arm by means of a wire. A number of more complicated arrangements were tried, but none seemed to give more uniform results than this simple contrivance. The tests were made with five different weights — 0.75, 1.00, 1.25, 1.50, 1.75 pounds, respectively. One hundred grains were counted out for each weight, and the hardness obtained by opening the jaws of the pincers just wide enough to insert the grain between them, and then allowing the weight to settle gently. The grains remaining unbroken by each weight were set aside and counted. The work was done under as nearly uni- form conditions as possible. The authors are inclined to doubt the fact that the hardness of the grain bears any very definite relation to the milling value. If such were the case, one would expect to find the varie- ties under such a test as this arranging themselves in nearly the same Fig. 13. — Showing apparatus used in testing hardness of kernels. order as the results obtained on the mill, and this can not be said to have been the case in the case of individual samples, although it must be admitted that the general trend of results points in that direction. The facts which are evident from this trial are as follows ; within the varieties individually the larger the grain the harder, which it will be noted is in the same direction as the flour yield. This appears to be true in each one of the varieties tested, without exception. Again, the greater the weight per bushel within the variety the harder the kernel. This, of course, means that the more dense the kernel the greater is its weight per bushel, other things being equal. Thus, between two lots of wheat of the same kind of different-sized kernels one would expect to find the larger-sized kernels harder, and it is quite evident that the larger-sized kernels will also give a greater flour yield. The quality of the flour, however, is quite apart from this general statement. As between the varieties it is to be noted that the following order is shown ; Sonora, Little Club, Australian, and Bluestem. This is quite a different order than would probably be assigned to these grains by a 336 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. miller, who would probably place them in the following order from a milling standpoint, Australian, Bluestem, Sonora, Little Club. There is little question but what the above-named figures represent the relative hardness of the varieties when expressed in actual weights, which would make it appear that the action under the rolls involves other factors besides the hardness, for it is the action under the rolls, which the miller has learned from long experience, which is likely to govern him very much wmen he attempts to judge of hardness by biting the grain ; and the difference between the white wheats is so slight, that he is uncon- sciously influenced almost altogether by the results of his experience with the grains under the rolls, rather than by the real hardness of the kernel. Indeed, one would expect the Sonora grains to be the harder from their general appearance, and from their usually higher bushel weight. The grains are small and dense, have a thin, smooth, glossy bran and more than make up in weight for what they lack in size, and this greater density is shown in their relative hardness as compared with the other varieties tested. THICKNESS OF BRAN. The thickness of the bran is recognized by millers as having more or less to do with the milling characteristics of wheats, and some prelim- inary work was undertaken in connection with these investigations towards a measurement of the thickness of the bran of the varieties of wheat under trial. For this preliminary work ten typical heads of "White Australian were selected for examination. Answers to two questions were sought : First, is the thickness of the bran fairly uniform in the same kernel ; second, is the thickness of the bran of kernels from different parts of the same head fairly uniform ? Preparation of the Grain. — To toughen the grain for section cutting it was first soaked in water, and then allowed to dry thoroughly on the slide. The section was cleared with clove oil, and to free the prepara- tion from air bubbles the dry section was treated with alcohol just before treatment with clove oil. The drawing was done by the aid of a camera lucida attachment to the microscope. An outline of the outer and inner edges of the bran was drawn, and the average width determined by measurement. Meas- urements were made at three points upon each grain on cross sections made at the ovary end of the kernel, at the center and at the beard end of the kernel, about 20 measurements being made upon the bran of each cross section. In all 60 kernels were thus examined,. 2 grains being taken from the top, 2 from the bottom and 2 from the center of each of the 10 heads. Bulletin 212] CALIFORNIA WHITE WHEATS. 337 Of these three fourths of the thickest sections were at the beard end of the kernels, but not much variation appeared from the center to the ovary end. TABLE VII— SHOWING MEASUREMENTS OF THICKNESS OF BRAN IN TEN HEADS OF WHITE AUSTRALIAN WHEAT. A. Ovary end. Beard end. end. Middle. Beard end. Third kernel from top of head— 1 2 Middle of head — 1 2 Third kernel from bottom of head 1 2 Third kernel from top of head— 1 2 Middle of head— 1 2 Third kernel from bottom of head 1 2 r< 1 2 Id 1 2 r< 1 2 Third kernel from top of head— 1 2 Middle of head— 1 2 Third kernel from bottom of head 1 2 2.8 3.3 3.4 2.5 2.4 3.4 3.1 3.6 2.9 2.4 3.7 2.7 3.6 2.7 3.6 3.8 3.1 3.2 3.3 2.8 3.1 3.4 3.5 2.9 3.1 3.1 3.4 3.8 3.0 2.8 c. D. 3.0 3.5 2.7 2.6 3.0 3.1 2.9 3.1 I 3.1 2.9 3.9 3.0 3.6 2.8 3.4 3.8 2.9 2.4 2.8 2.7 2.6 2.7 3.1 3.3 2.9 2.7 3.3 2.8 2.7 3.4 3.3 4.0 3.0 3.5 3.5 2.8 2.9 3.5 2.7 3.5 2.9 E. Third kernel from top of head— 1 2.6 2.6 2.6 2.4 2.5 2.7 2.8 3.1 3.0 2.9 3.3 3.2 2.7 2.7 3.6 3.1 3.5 3.5 2.9 2.7 3.2 3.0 2.9 2.5 2.8 2.6 3.3 3.1 3.7 2.9 3.7 2 3.3 Middle of head — 1 _ 3.3 2 _ _ ___ 3.8 Third kernel from bottom of head— 1 ___ 3.3 2 3.1 H. 3.0 2.9 3.3 3.0 3.1 2.7 2.5 3.8 3.2 3.0 3.0 3.2 3.7 4.0 3.7 3.5 3.8 3.3 2.8 3.3 2.6 2.4 3.2 3.5 3.4 3.9 3.0 3.0 3.5 2.9 3.3 3.6 3.7 3.4 3.3 338 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. TABLE VII — Continued. I. J. Ovary end. Middle. Beard end. Ovary end. Middle. Beard end. Third kernel from top of head— 1 2.5 2.8 2.9 2.9 2.7 2.3 3.2 2.6 2.8 2.9 3.3 3.0 3.5 3.0 3.9 3.6 2.9 3.6 1 2.6 2.8 3.0 3.2 2.9 2.9 3.2 2.8 2.8 3.1 3.0 3.0 3.9 2 3.1 Middle of head — 1 3.9 2 3.5 Third kernel from bottom of head— 1 3.5 2 3.2 Collecting these results so as to show the variation a little more closely by averaging the measurements for each of the two grains from the several heads we have as follows : Third Kernels from Top of Head Head. A B O D E F G H I J Average. Kernel No. 1 Kernel No. 2 Average 3.16 3.33 3.14 2.76 2.86 2.81 3.16 3.13 3.09 2.66 2.73 2.69 2.70 2.80 2.75 3.13 2.86 2.99 2.96 3.03 2.99 3.13 2.73 2.92 3.06 2.80 2.93 3.23 2.90 3.06 2.995 2.917 2.956 Middle Kernels. Kernel No. 1. Kernel No. 2. Average 3.33 3.33 3.30 3.03 3.06 3.10 3.10 2.96 3.06 2.80 3.26 3.30 3.90 3.40 3.60 3.16 3.20 3.13 3.23 3.26 3.33 3.16 3.08 3.03 2.93 3.18 3.55 3.38 3.16 3.24 3.284 3.147 3.215 Third Kernel from Bottom of Head. Kernel No. 1. Kernel No. 2. Average 3.33 3.43 3.10 3.23 3.26 3.23 3.16 2.80 3.10 3.13 3.30 2.83 3.16 3.30 3.26 3.46 2.96 2.96 3.13 3.03 3.38 3.16 3.19 2.32 3.11 3.06 3.23 3.36 2.96 3.08 3.176 3.140 3.158 These figures indicate that there is considerable variation in the thick- ness of the bran on different parts of the same kernel, and that the bran from kernels on the center of the head is thicker than in kernels from either end. Bulletin 212] CALIFORNIA WHITE WHEATS. 339 Chart showing Thickness of Bran of White Australian Wheat Third Kernel from Top of SpiKe Middle Kernel Third Kernel from Bottom of Spike. 340 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. Similar measurements were made in the case of Little Club, which gave the following average results : Ovary end. Center. Beard end. Average. Top of head Middle of head 3.0 - 3.1 - 3.1 - 3.06 3.3 - 3.3 + 3.3 - 3.30 3.4 + 3.6 3.5 + 3.50 3.23 3.33 Bottom of head _ _ 3.30 Mean _ _ 3.29 Here again the same facts appear as in the case of "White Australian, namely, as to the individual kernel, the bran was the thickest at the brush end ; and with reference to the location on the spike, the thickest bran was found on the kernels from the middle of the head. THE CHEMICAL COMPOSITION OF WHEATS. The question of the relation of the chemical composition of wheats to their baking or milling value has been one which has attracted the atten- tion of chemists both in this country and abroad for many years, but up to the present time its complete solution has baffled their skill. While this is true, some advance has been made and certain factors which undoubtedly have a bearing upon their quality as related to bak- ing have been determined; but, nevertheless, it must be admitted that we are still far from a very intimate understanding of the true relation of these factors. It is probably unnecessary to devote any space to a discussion of the real practical value which chemical data would have, provided they could be correlated on a correct basis with the baking value of wheat or flour. It is not likely that they would have a very close relation to the mill- ing value except as such value is related to the baking value, because the milling value per se may be quite independent of the baking value of the flour. The milling qualities of a wheat are almost entirely dependent upon the physical characteristics of the grain, while the bak- ing characteristics of the flour are evidently quite closely related to cer- tain chemical factors. The miller is primarily interested in a large yield of flour of good appearance, while the prime question with the baker is that the flour shall have a sufficient "strength" for his special purpose. A wheat may have excellent milling qualities and still yield a flour quite unsatisfactory to the consumer, and vice versa. The dormer condition is far loo often the case with the California wheats, Bulletin 212] California white wheats. 341 and this was the basal reason for the inauguration of the cereal investi- gation in which this Station is now engaged. It is quite obvious, then, that the term "strength" and "quality" are not interchangeable, but have quite distinct meanings. The former refers to something which is rather definite in nature, notwithstanding we have not as yet fully ascertained what are the factors which deter- mine the so-called ' ' strength. ' ' The ' ' quality " of a flour depends much upon the purpose for which it is intended. It may be very high for pastry, but very poor for bread. A flour which has very high 1 ' strength ' ' is usually of lower ' ' quality ' ' for pastry purposes than one of much lower strength. On the other hand, high "strength" is extremely desirable, and well-nigh essential, for the making of good light bread, or macaroni. The general composition of wheats does not differ materially from that of other organic bodies, in that it is made up of several different groups of constituents, viz., moisture, ash, crude protein, fats, and carbohydrates. These are not distinct and separate compounds, but are groups of bodies having similar properties or food value within each group. Thus, for instance, the term carbohydrates is a general term, embracing a large number of substances, as sugars, starches, certain gums, etc., while protein is the name of a general class of bodies con- taining nitrogen as an essential ingredient, examples of which are albu- min or the white of eggs, the lean meat of animal bodies, the gluten of flour, etc. The composition may be graphically represented as follows : r 1 Gliadin. j Glutenin. Nitrogen- . Proteids \ | Non- C Water. ous i Edestin. I (. Proteids J Leucosin. ' Organic - ( Amides. STHEAT. { f Fats or Ether Ext. 1 Dry Non- | [_ Matter. Nitrogen- i C Nitrogen- cms | Carbo- ^ hydrates | free Ext. J Mineral— -Ash. j Crude [ Fiber. In all cases water is present. In many instances this is very evident, as in grass, beets, turnips, etc., while in other material it is not so evi- dent, yet when they seem perfectly dry under ordinary conditions, there is from 5 to 10 per cent, moisture present. This water has no more food value than that taken from wells or streams. It is, however. a necessary constituent of organic material. Moisture is determined in the laboratory by heating the material for a long time at the tempera- ture of boiling water. After the moisture has been driven off there is left the dry matter, which is partly organic and partly mineral in its composition. 342 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. The mineral matter of plants is expressed by the term ash. It is the residue left after burning to perfect whiteness. The organic matter embraces two well-marked classes, viz., those con- taining the element nitrogen, nitrogenous ; and those which lack nitro- gen, non-nitrogenous. Of all the material composing a foodstuff, the nitrogenous matter is the most important. It embraces both proteids and non-proteids, which, however, are not usually separated, but classed together as protein. The nitrogenous compounds of wheat consist principally of proteids of which five have been recognized and described by Osborne and Voor- hees as follows : 1. A globulin, soluble in saline solutions, and not coagulable at a tem- perature below 100° C. This constitutes 0.6-0.7 per cent, of the grain. 2. An albumin, coagulable at 52° C. It differs from animal albumin in several important particulars. It constitutes from 0.3-0.4 per cent, of the kernel. 3. A proteose, which is extracted from the wheat by dilute saline solu- tions after removing the globulin by dialysis and the albumin by coagu- lation. It constitutes 0.2-0.4 per cent of the kernel. 4. Gliadin, a proteid body soluble in dilute alcohol, and forming nearly one half of the total proteid matter of the kernel. 5. Glutenin, which is insoluble in water, dilute saline solutions, and dilute alcohol, and which, together with gliadin, forms nearly the entire proteid content of the wheat kernel. Gluten. — Chemists divide the above indicated proteids into two gen- eral classes, viz., gluten and non-gluten proteids. Gluten is a mixture of gliadin and glutenin. It is the amount and quality of gluten which gives to flour ability to rise into a light and spongy loaf of bread. In the process of bread making, the carbonic acid gas liberated during the fermentation period is imprisoned by the sticky, elastic gluten, and as the gas expands, causes the bread to become porous. Crude gluten can be obtained either from a wheat meal or flour by washing out the starch and water-soluble portions from a dough made by kneading the meal with water. In this condition it will carry about two thirds of its weight of water and certain impurities which are fairly constant in different samples. "A good gluten has a light yellow color, is tenacious and elastic, while poor gluten is dark in color, sticky but not elastic."* As the gluten of wheat is that constituent which causes the flour to be strong, wheats to be of high baking quality should carry a high per- centage of gluten. This high percentage of itself, however, is not suffi- cient, since it is found that glutens differ much in quality, some are tough and elastic and others not. Again the latter generally are able * Hunt's Cereals in America, page 41. Bulletin 212] CALIFORNIA WHITE WHEATS. 343 to retain a very much smaller amount of water, resulting in a corre- spondingly less number of loaves per barrel of flour. To be of high quality a gluten should be highly elastic. It has been claimed by some writers that the quality of a gluten is much dependent upon the proportion of the gliadin and the glutenin present. M. E. Fleurent, a French investigator, states that the most favorable ratio of gliadin to glutenin in flour is 75 to 25. Snyder, formerly of the Minnesota Experiment Station, states that 80 to 85 per cent of the total protein should be gluten, and of this the proportion of gliadin to glutenin should be 60 to 65 per cent. Later work of Snyder, however, seems to cast some doubt as to the value of this matter of proportion of gliadin to glutenin, for, in 1905, a year later than the former statement, he writes : ' ' As our work on this point extends over a number of years it appears that it is more a ques- tion of total gliadin than the ratio of gliadin to glutenin." The results presented in the later pages of this bulletin seem to bear out this latter statement of Snyder and to cast grave doubt upon the possibility of correlating the gliadin-glutenin ratio closely with the bread-making value of a wheat or flour. Fats. — Nearly all foodstuffs contain more or less fat. Here, again, the term is not used in as definite a sense as in ordinary language, but rather refers to a class of bodies which have a similar composition, and since they are determined by extraction with ether, many chemists pre- fer to use the name Ether Extract. It really denotes more than fat in the case of green foodstuffs, as the coloring matter and certain gums are extracted at the same time, but in grain the extract is nearly all fats and oils. These do not differ in any essential particular from the ani- mal fats and oils, which all belong to a class of bodies known as glycer- ides. The fat of wheat is not a very important element in determining its value. The Carbohydrates are usually separated into Crude Fiber, and another class called Nitrogen-free Extract. The former is the woody tissue of the plant, which remains after successive boilings with a weak acid and a weak alkali. It is found principally in the bran. Carefully conducted experiments show that even this woody fiber has a nutritive value, a small quantity usually being digested. Still the value of food- stuffs usually varies inversely as the amount of crude fiber present. The Nitrogen-free Extract is composed of a number of substances as starch, sugar, dextrin, and gums, grouped together because similar in composition. Starch is the most important of the carbohydrates of wheat and con- stitutes from 64 to 70 per cent, of the kernel. It is, of course, of great importance as the principal foodstuff in bread. Sugar and dextrin are 344 UNIVEESITY OF CALIFORNIA— EXPERIMENT STATION. other compounds which are present in wheats in quite small quantities. In sound wheat if sugar be present it should be in the form of cane sugar. Should, however, the sugar be in the form of maltose it would undoubtedly indicate a partial hydrolysis of starch and would be object ionable. The same may be said with regard to the presence of dextrin. Incomplete as are the present laboratory methods, they still furnish results of considerable value in a broad classification of wheats and flours, even if failing to distinguish between two samples of approx- imately the same ' ' strength. ' ' With the idea of obtaining more information relative to the chemical characteristics of the common California white wheats, the samples dis- cussed previously, as well as some others, were subjected to chemical analvsis. THE METHODS FOR CEREAL ANALYSIS. The methods of analysis adopted for this work were adapted from those given in Bulletin 107. of the Bureau of Chemistry, United States Department of Agriculture, and the work of Teller, and are set forth below. Moisture. — Dry 2 to 3 grams of the material for five hours at the temperature of boiling water. Use the aluminum moisture dishes provided for this purpose. ( Note. — If fat is to be determined the dried material from the moisture determination can be used. ) Ash. — Char 2 grams of the material, if a wheat meal, or 3 grams if a flour, and burn to whiteness at the lowest possible red heat. If a white ash can not be obtained in this manner, exhaust the charred mass with water, collect the insoluble residue on a filter, burn, add this ash to the residue from the evaporation of the aqueous extract, and heat the whole to a low redness till the ash is white or nearly so. Great care has to be taken with these wheat products not to overheat at the start. It must under no circumstances be fused if phosphoric acid is to be determined in the ash, other- wise fusing is allowable, the loss being so small as to be negligible.* * Leavitt & Le Clerc, "Loss of Phosphoric Acid in Ashing Cereals," Jour. Am. Chem. Soc, Vol. XXX, No. 3, p. 391. SCHEME FOR NITROGEN DETERMINATION. The basal scheme for nitrogen determination for various protein com- pounds is as follows : Determine total nitrogen x Determine non-gluten nitrogen (=salt soluble X. — constant *) y Difference = gluten nitrogen = x — y Determine gliadin nitrogen (=alcohol soluble) f z Difference=glutenin nitrogen =(# — y) — z * Constant for soft wheat meals=.15. Constant for durum wheat meals = .20. Constant for flour=.22. Thes<- constants represent the average amount of gliadin nitrogen that will be found in the salt solution. j- Strictly speaking, the gliadin nitrogen should be corrected for the amid nitrogen m. bul for mosl practical purposes this may be neglect*'! Bulletin 212] CALIFORNIA WHITE WHEATS. 345 Detailed Outline of Methods. Total Nitrogen — Gunning Method: In a digestion flask (Kjeldahl) place one gram of the material to be analyzed. Add 10 g. of powdered potassium sulfate and about 20 cc. of concentrated sulfuric acid. Digest as in the ordinary Kjeldahl process, starting with a comparatively low temperature and gradually increasing. Digest until the mixture is colorless. Do not add either potassium permanganate or potas- sium sulfid. Dilute, neutralize and distil as in Kjeldahl method. In neutralizing it is convenient to add a few drops of phenolpthalein to serve as an indicator. Use 10 cc. n/4 hydrochloric acid, dilute with an equal volume of water for collect- ing the ammonia and distil off about three fourths of the contents of the distillation flask. Use n/10 ammonia for titrating back the acid, with cochineal as an indicator. Note. — For further details see Official Method, Bui. 107, page 7. (2) Total Proteids. Nitrogen determined as above x 5.68 = total proteids. (3) Gliadin. Weigh out 21 gms. of flour into a small flask holding somewhat more than lOOcc. Add 100 cc. of 70 per cent, alcohol and shake thoroughly for 15 minutes. Allow to stand 18 hours and filter into a Kjeldahl digestion flask with a short neck. Wash the residue with 100 cc. of 70 per cent, alcohol. Add to the total filtrate 10 cc. of concentrated sulfuric acid and distill off the excess of alcohol, con- tinuing the distillation until fumes appear. Add 10 cc. more of concentrated sulfuric acid and finish the determination of nitrogen by the Gunning method. The nitrogen X 5.68 = proteid soluble in alcohol. With old and unsound flours a correction must be made for soluble amid bodies. (4) Non-Gluten Nitrogen. Place 4 grams of the material in a 200 cc. flask. Add about 15 cc. of a 1 per cent, solution of sodium chlorid and shake thoroughly. To the resulting homogeneous mass, add enough of the same solution to make exactly 100 cc. of the salt solution as a total amount. Shake the contents of the flask in a shaker for 6 hours. After allowing it to stand over night to settle, filter off 50 cc. of the liquid through a 12£ cm. dry filter, pouring back the first portion of the filtrate until it filters clear and determine the nitrogen therein by the Gunning method. On col- lecting this 50 cc. with a few cubic centimeters of washings in a Kjeldahl flask and adding 20 cc. concentrated sulfuric acid, the water can readily be boiled off, especially if the flask be protected from the naked flame. When the acid ceases to foam it is cooled slightly, sulfate of potash added and the nitrogen determination completed in the usual way. After adding the sulfate of potash, the time required for the diges- tion is but a few minutes. A small percentage of gliadin nitrogen will be included in the above determina- tion. Experience has shown that this amounts to about .15 per cent, for white wheat meals and is quite constant. This factor (.15%) should be subtracted from the nitrogen per cent, as determined in the above procedure. For factors to use with other wheats see page 344. The difference is called Non-gluten Nitrogen. The protein corresponding to this nitrogen is calculated by multiplying by 5.68. (5) Glutenin. For most purposes the difference between the gluten nitrogen and the gliadin nitrogen, as determined above, may be considered glutenin nitrogen. For more accurate work, however^ the glutenin nitrogen may be determined as follows : The residue from the gliadin determination is washed with 70 per cent, alcohol until the washings no longer react for proteids. Transfer it to a flask and add 200 cc. of a 5 per cent, solution of sodium chlorid to remove globulin and other proteids. After two hours extraction the residue is washed with distilled water and transferred to a flask, 250 cc. of a 2 per cent, solution of potassium hydroxid added and after 3 hours' extraction the solution is filtered and the nitrogen determined in 200 cc. of the filtrate in the usual way. (6) Amid Nitrogen. From 100 cc. of the salt extract precipitate all the proteids by adding 10 cc. of a ten per cent, solution of phospho-wolframic acid, made by dis- solving the pure solid in distilled water. (Note. In case of bran, it may be nec- essary to add more of the phospho-wolframic solution.) Allow to settle before filter- ing and determine the nitrogen in the clear filtrate. In order to secure a clear filtrate it will doubtless be necessary to allow the solution to stand over night in order to obtain a clear supernatant liquid. On collecting this (50 or 100 cc. with a few cubic centimeters of washings) in a Kjeldahl flask and adding 20 cc. of concentrated sul- furic acid the water can be readily boiled off, especially if the flask be protected with a thin sheet of asbestos. When the acid ceases to foam it is cooled slightly, sulfate of potash added and the nitrogen determination completed in the usual way. After adding the sulfate the time required for digestion is but a few minutes. 3— b212 346 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. (7) Edestin and Leucosin Nitrogen. To 50 cc. of the clear salt extract, obtained as described above, add, in a 500 cc. Kjeldahl digestion flask, 250 cc. of pure 94 per cent, alcohol (188 per cent, proof, re-distilled). Mix thoroughly and allow to stand over night. Collect the precipitate on a filter (10 cm.) of good quality, return to the flask, and determine the nitrogen, making proper correction for nitrogen in the filter. Note. — If desired these two proteids may be separated by coagulating the leucosin at 60 °C. and precipitating the edestin by adding alcohol to 50 cc. of the clear filtrate as before. The nitrogen in each precipitate may then be determined. (8) Baker's Sponge Test. — 100 grams of flour are weighed into a wide porcelain dish or bowl. A part of the water (50 to 65 cc.) necessary to make a stiff dough is run in from a burette. In this is dissolved 5 g. of sugar and 5 g. of compressed yeast. The flour is then stirred in with steel spatula and more water added until dough of standard stiffness is obtained. Amount of water used for dough recorded. The dough is now placed in tubes of about 4 inch diameter, graduated into cubic centimeters. These tubes are now set in water at 90 °F. and the dough allowed to rise. It must be constantly watched until the maximum height is reached and the dough falls, when the time required to rise and the volume in cubic centimeter is recorded. This is repeated and the volume and time again recorded. By dividing the volume of loaf, to which 100 grams of flour rises, by the percentage of gluten in the flour, the volume of loaf produced by each gram of gluten is found. (9) Acidity. — In a porcelain casserole place 5 grams of flour, and gradually mix with about 50 cc, of distilled water freed from carbon dioxid by previous boiling. When a perfectly homogeneous mixture has been obtained add a few drops of phenolpthalein, and titrate with n/50 NaOH. It is unnecessary to filter previous to titration. Calculate results to sulfuric acid. (10) Wet Gluten. — Weigh out 25 grams of the sample, moisten with 15 to 18 cubic centimeters of water, knead to a stiff dough. Work thoroughly so as to bring all gluten into active contact. Allow to stand for one hour. Holding the mass in the hand under a slow stream of cold water gently pull and knead at the same time until the starch and all soluble matters are washed out. It is well to conduct the work over a fine sieve to prevent the loss of small particles of gluten. Then place in cold water and allow to stand for one hour, finally remove from the water, knead well in the hands, frequently drying the hands upon a towel. During the kneading of the gluten, manipulate it in such a way as to ultimately bring all parts of the gluten on the outside. When all the free water has been removed, roll the mass into a ball and weigh either upon a counterpoised card or in a flat-bottom dish. Note should be made of the color and general stiffness as shown by the way it stands up upon the card. The stiffer the gluten the more globular the mass. (11) Dry Gluten. — After weighing, introduce the ball of wet gluten into a drying oven at a temperature of boiling water and try to constant weight. The time required will be not less than fifteen hours, cool and weigh. (12) Water Capacity. — The difference between wet and dry gluten equals the water holding power. Record this, as one part gluten holds x parts of water. (13) Ether Extract. — (Fat) Extract from 2 to 3 grams of the substance used for the determination of moisture, with anhydrous alcohol-free ether for sixteen hours. Filter off the solid residue through a small filter paper into a tared flask. Distil off the ether, and dry the extract to constant weight. This work is most con- veniently done in a small wide-mouthed Erlenmeyer flask. Or, the residue can be collected in a tared Gooch filter, dried as in the moisture determination, and the loss in weight regarded as ether extract. Note. — The ether used for this work must be strictly anhydrous. To prepare this, wash any of the commercial brands of ether with two or three successive portions of distilled water, and add solid caustic potash or soda until most of the water has been abstracted from the ether. The final traces of moisture can be removed by adding to the partially dried ether carefully cleaned metallic sodium, cut in small pieces, until no more hydrogen gas is evolved. The dehydrated ether should be kept over metallic sodium. Bulletin 212] CALIFORNIA WHITE WHEATS. 347 A TRIAL OF THE POLARISCOPIC METHOD POR THE DETERMINATION Of GLIADIN. The use of the polariscope has been suggested for the determination of gliadin in cereal products as offering a method which would reduce the time required by the ordinary Gunning-Kjeldahl operation, and at the same time be sufficiently accurate for technical purposes. With the idea of satisfying ourselves upon the applicability of the method, as applied to the products in hand, comparative trials of this method were made against the ordinary Gunning-Kjeldahl procedure. This is more rapid than the regular method and is recommended for general work when there is sufficient material. Weigh out 15.97 grams of the material and digest over night in 100 cc. 70 per cent alcohol. The flask should be agitated thoroughly at intervals of one half -hour for a period of two hours. Filter to a clear solution, protecting from evaporation as much as possible. Polarize in a 220 mm. tube. The reading will probably be a minus one. Correct for sugar by adding to 50 cc. of the filtrate sufficient mercuric chlorid (concentrate solution) to precipitate all the proteids : Make to 55 and polarize again. The range of material covered by these trials was somewhat differ- ent than those mentioned in the original article by Snyder.* The first series of analyses were made upon soft wheat meals. The results are set forth below : Gliadin nitrogen calculated to dry matter. Laboratory number. By Polariscope method. By Gunning method. Difference. 19 0.72 0.56 0.46 0.38 0.42 0.42 0.54 0.49 4.40 0.43 0.44 0.39 0.43 0.49 0.64 0.55(?) 0.53 (?) 0.50 249 + 02 254 -.03 257 - 02 265 -.01 266 -.02 268 0.39 0.38 0.49 0.57 0.39 0.39 0.49 .00 270 -.05 288 .00 290 -.07 313 -.16 322 -.14 326 -.11 The above determinations were made upon soft white wheat meals. In this lot of samples the gliadin determination by the Gunning method had already been made several weeks before the trial of the polariscope method. Determinations were made by the polariscope method on the basis of the changed moisture content of the sample, and the results in each case calculated to dry matter for comparison. Further, the methods were H. Snyder in Jour. Am. Chem. Soc, Vol. XIX, Xo. 12. 346 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. operated by different parties, so there were undoubtedly introduced into the operation greater differences in the manipulation of securing solu- tion of the gliadin than if the two operations had been conducted by the same person. Notwithstanding these sources of error it will be noted, that with the exception of Nos. 313 and 322, concerning which there was previously existing some doubt as to the accuracy of the original determination, the polariscopic method gave results which are within the range of error of most operations. The above results not being quite satisfactory, the comparison of methods was carried further with the same class of material, the sample operated upon in the one method being ta'ken from the same solution as in the other, one portion being used for polarization and another treated by the Gunning method. The solution of gliadin in these trials was effected by digesting in the cold, as described by Snyder, 15.97 grams of the material in 100 cc. of 70 per cent, alcohol. The flask was shaken at intervals of half an hour for two hours, and left overnight before filtration. Ten cubic centimeters of this solution were used for treat- ment by the Gunning method, after first driving off the alcohol by evap- oration. By this procedure one would expect somewhat closer results than by the former. SOFT WHEAT MEALS. FLOUR. By By By By Polariscope Gunning Difference. Polariscope Gunning Difference. method. method. method. method. 0.90 0.91 -.0! 0.77 0.75 + .02 0.70 0.69 + .01 0.59 0.57 + .02 0.86 0.90 - .04 0.51 0.48 + .03 0.81 0.75 + .06 0.46 0.43 + .03 0.64 0.63 + .01 0.62 0.55 + .07 0.70 0.70 .00 0.77 0.70 + .07 0.66 0.69 - .03 0.86 0.84 + .02 0.92 0.94 - .02 0.64 0.69 - .05 Average +0.04 0.95 0.94 0.59 + .01 - .02 0.57 0.55 0.60 - .05 DUR JM WHEAT MEALS. 0.73 0.71 0.60 + .02 + .02 0.62 0.62 0.66 - .04 0.84 0.83 + .01 0.53 0.56 - .03 0.77 0.78 - .01 0.90 0.92 - .02 0.95 0.94 + .01 0.88 0.85 + .03 0.70 0.76 - .06 0.81 0.78 + .03 0.66 0.69 - .03 0.70 0.70 .00 0.75 0.75 .00 0.73 0.74 - .01 0.79 0.83 - .04 0.77 0.78 + .01 0.59 0.62 - .03 0.62 0.60 + .02 0.81 0.78 + .03 0.59 0.57 + .02 0.61 0.64 .00 0.64 0.60 - .04 0.64 0.60 0.58 - .04 Average -0.02 \\ < -0.03 Bulletin 212] CALIFORNIA WHITE WHEATS. 349 In but three cases out of the forty-five last stated does the difference between the two methods exceed 0.05, which is certainly as close as one can expect ordinary technical work to be done, and as between two sam- ples is undoubtedly within the limits of accuracy of sampling large lots. A still further test of the method was given by making a gliadin deter- mination upon a gluten flour in which the Kjeldahl method showed 3.32 per cent, of gliadin nitrogen. The polariscopic method showed 3.45 per cent. Considerable difficulty was experienced at the outset in securing a clear solution for filtration, but this was finally overcome by avoiding excessive agitation. Snyder remarks that in the case of flours analyzed by him, and prob- ably grown in the middle west, "the combined alcohol soluble carbohy- drates and non-gliadin proteins of the alcoholic solution affect the polar- ization to only a slight extent, ' ' and states that after the gliadin protein was precipitated the non-gliadin rotary bodies showed a reading of less than 0.20 on the sugar scale. In our experience with the method it was always found necessary to make two polarizations, the first on the original solution, and the second after separating the protein bodies by the use of a concentrated solution of mercuric nitrate, and then making the required correction to give the true gliadin reading. This was particularly true in the case of wheat meals where the aver- age difference between the two polariscope readings was 1.05 on the sugar scale corresponding to 0.21 per cent, on the gliadin scale, the range of differences on the sugar scale being from 0.08 to 2.75. In the case of flours, unless extreme accuracy is required, the correction could be neglected inasmuch as the error is much less, not exceeding 0.04 per cent, of the gliadin scale. The writers are strongly impressed with the idea that the method is worthy of a much more extended use than it has so far had, and that if precautions are taken to correct for the eifect of other optically active bodies, there are fewer opportunities for error than with the ordinary method of nitrogen determination. NITROGEN OF COMPOUNDS SOLUBLE IN ONE PER CENT. SODIUM CHL0RID SOLUTION. Before reaching a decision as to the factor to be subtracted from the nitrogen found in the salt extract, several separations of the nitrogenous ingredients of this extract were made. Teller from his elaborate work upon this point, suggested that the factor .27 per cent, be used, and pro- ceeded upon that basis. In discussing this question he states, however, that "two other samples showing an unusually low difference (that is, gliadin per cent, in salt extract. G. W. S.) are white wheats, each of 350 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. which contains a very low per cent, of gliadin. ' ' He also intimates that another factor than .27 might be preferable for such wheats. It was with the idea of ascertaining what this factor should be that the sep- aration of the protein compounds was undertaken. The procedure followed was as set forth under the portion of this bulletin headed "Methods of Analysis of Cereal Products." First of all, to ascertain the effect of different methods of shaking to secure solution of the compounds, comparative trials were made (1) by shaking at intervals of half hours for a period of six hours, and (2) shak- ing in a mechanical shaker continuously for a period of six hours, the results are given in detail in the following table : TABLE VIII. — SHOWING NITROGEN COMPOUNDS IN WHEAT MEALS SOLUBLE IN ONE PER CENT SODIUM-CHLORID SOLUTION. Hard Wheat Meals. 2 c s a How Treated. c 3 o 2. 3 w 3 g, (6 3 d to s 2 B. £' 3 3 2 IS? 723 723 Shaken at intervals for 6 hours Shaken continuously for 6 hours— 11.07 11.07 .43 .53 .17 .21 .06 .06 .20 .26 .224 .291 724 724 Shaken at intervals for 6 hours Shaken continuously for 6 hours__ 10.70 10.70 .49 .53 .17 .24 .07 .06 .25 .23 .280 .257 727 727 Shaken at intervals for 6 hours Shaken continuously for 6 hours__ 10.61 10.61 .42 .49 .22 .20 .06 .06 .14 .23 .159 .257 728 728 Shaken at intervals for 6 hours Shaken continuously for 6 hours__ 10.56 10.56 .46 .51 .23 .20 .06 .07 .17 .24 .190 .269 731 731 Shaken at intervals for 6 hours Shaken continuously for 6 hours__ 10.40 10.40 .48 .52 .20 .21 .08 .07 .20 .24 .223 .269 735 735 Shaken at intervals for 6 hours Shaken continuously for 6 hours.- 10.70 10.70 .45 .51 .21 .20 .08 .06 .16 .25 .179 .280 Average at 6-hour intervals Average continuous shaking 10.67 10.67 .45 .51 .20 .21 .07 .06 .19 .24 .209 .270 Soft Wheat Meals. 232 Shaken at intervals for 6 hours.— 232 Shaken continuously for 6 hours. 237 Shaken at intervals for 6 hours— 237 Shaken continuously for 6 hours. 240 Shaken at intervals for 6 hours— 240 Shaken continuously for 6 hours. 242 Shaken at intervals for 6 hours— 242 Shaken continuously for 6 hours. 245 Shaken at intervals for 6 hours— 245 Shaken continuously for 6 hours. Shaken at intervals for 6 hours— 246 Shaken continuously for 6 hours. Average at intervals for 6 hours. Average continuous shaking 11.42 11.40 .41 .35 .16 .14 .08 .07 .17 .14 11.52 11.49 .39 .39 .17 .14 .08 .08 .14 •17 11.85 11.90 .35 .42 .15 .18 .07 .08 .13 .16 11.36 11.32 .46 .48 .17 .18 .08 .07 .21 .23 10.73 11.75 .43 .42 .17 .15 .07 .07 .19 .20 10.70 10.75 .35 .41 .15 .18 .05 .07 .15 .16 10.27 11.43 .40 .41 .16 .16 .07 .07 .16 .18 .191 .158 .158 .192 .147 .181 .236 .259 .212 .226 .160 .179 .187 .199 Bulletin 212] CALIFORNIA WHITE WHEATS. Soft Wheat Flours. 351 2 a H - > g o c B s* How Treated. 2. en" i E 3 _ ~ — J - CD B. I a •Oft 19,24 Shaken at intervals for 6 hours 10.99 .36 .12 .03 .21 .235 19,24 Shaken continuously for 6 hours.. 10.99 .36 .10 .04 .22 .250 248 Shaken at intervals for 6 hours 11.35 .36 .12 .03 .21 .237 248 Shaken continuously for 6 hours__ 11.35 .36 .11 .03 .22 .249 266 Shaken at intervals for 6 hours 11.25 .31 .09 .03 .19 .214 266 Shaken continuously for 6 hours.. 11.25 .31 .08 .03 .20 .226 268 Shaken at intervals for 6 hours 11.13 .29 .09 .02 .18 .202 268 Shaken continuously for 6 hours.. 11.13 .31 .08 .03 ..20 .225 288 Shaken at intervals for 6 hours 10.40 .36 .12 .03 .21 .245 288 Shaken continuously for 6 hours.. 10.40 .38 .10 .03 .25 .279 512 Shaken at intervals for 6 hours 10.70 .41 .12 .02 .27 .302 512 Shaken continuously for 6 hours.. 10.70 .41 .13 .04 .24 .272 Average at 6-hour intervals 10.97 .35 .11 .03 .21 .237 Average for 6 hours shaking 10.97 .35 .10 .03 .22 .250 General average, intervals 10.64 .40 .16 .06 .19 .211 General average, continuous 10.64 .42 .16 .05 .21 .239 An examination of this table shows that the continuous shaking would have given slightly higher results, but they would not have been mate- rially changed by such procedure, and so far as the general run of tech- nical work is concerned the interval shaking is doubtless entirely satis- factory. Adopting as the basis of the work the classification of the proteids of wheat as previously set forth 7 a nextract was obtained from 4 grams of finely ground wheat meals by means of a 1 per cent, sodium chlorid solution and aliquot portions used for the direct determinations of total nitrogen, edestin and leucosin nitrogen, and of amid nitrogen. The difference between the sum of these, and the total, was presumed to represent gliadin nitrogen that had been dissolved by the salt solution. Throughout this work the shaking was done at intervals of a half hour for a period of six hours. 352 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. TABLE IX.— SHOWING NITROGEN OF COMPOUNDS SOLUBLE IN ONE PER CENT SODIUM CHLORID SOLUTION. 2 o H H el Q 1 1 p 5- ® u> 5" o. 3 3 & Name. c 3 j i 2. P l^ 5 O 1 W m 1 ^ 8° i •* s i 3 & i I 5 " I £ To? 1 205 205 206 206 212 212 231 231 232 232 233 233 237 237 242 242 245 245 240 240 Wheat meal Wheat meal Average Wheat meal Wheat meal Average — Wheat meal Wheat meal Average Wheat meal Wheat meal Average Wheat meal Wheat meal Average 12.00 11.89 11.945 12.28 12.21 12.245 11.63 11.55 11.59 11.85 11.68 11.765 11.42 11.37 11.395 Wheat meal 11.66 Wheat meal ._ _„ 11.84 Average 11.75 Wheat meal 11.52 Wheat meal 11.46 Average 11.49 Wheat meal _ 11.36 Wheat meal 11.28 Average ___ 11.32 Wheat meal .__ 10.73 Wheat meal 10.77 Average 10.75 Wheat meal __ 11.85 Wheat meal 11.95 Average 11.90 246 Wheat meal 10.70 246 Wheat meal .__ 10.81 Average ___ 10.755 247 I Wheat meal 11.30 247 Wheat meal 11.54 Average 11.42 248 Wheat meal 11.02 248 Wheat meal 10.97 Average 10.995 249 Wheat meal 11.10 249 Wheat meal 10.95 Average 11.025 254 254 Wheat meal 11.02 Wheat meal 10.66 Average 10.84 Grand average soft wheat meals__ 11.41 .35 .37 .36 .38 .37 .375 .46 .45 .455 .36 .39 .375 .41 .38 .395 .46 .48 .47 .39 .41 .40 .46 .46 .46 .43 .42 .425 .35 .34 .345 .35 .35 .35 .41 .39 .40 .35 .36 .355 .34 .35 .345 .35 .34 .345 .39 .16 .16 .16 .17 .17 .17 .17 .17 .17 .17 .17 .17 .16 .14 .15 .20 .20 .20 .17 .19 .18 .17 .17 .17 .17 .17 .17 .15 .15 .15 .15 .14 .145 .15 .14 .145 .15 .12 .135 .14 .13 .135 .12 .12 .12 .16 .08 .08 .08 .10 .10 .10 .15 .16 .155 .06 .07 .065 .08 .10 .09 .09 .09 .09 .085 .08 .07 .07 .07 .07 .07 .07 .05 .06 .065 .06 .06 .06 .04 .05 .045 .05 .06 .055 .05 .05 .05 .076 .11 .13 .12 .11 .10 .105 .14 .12 .13 .13 .14 .135 .17 .13 .15 .17 .18 .175 .14 .13 .135 .21 .19 .20 .19 .18 .185 .13 .12 .125 .15 .15 .15 .20 .19 .195 .16 .19 .175 .15 .16 .155 .18 .17 .175 .154 Bulletin 212] CALIFORNIA WHITE WHEATS. 353 TABLE IX (continued.) t 1 ~S i a a | I 1 .45 .19 .06 .20 ! .43 .17 .06 .20 .44 .18 .06 .20 .43 .19 .06 .18 .43 .17 .06 .20 .49 .17 .07 .25 .42 .22 .06 .14 .46 .23 .06 .17 .48 .22 .07 .19 .48 .20 .08 .20 ' .45 .21 .08 .16 .45 .201 .066 .189 .36 .12 .03 .21 .36 .12 .03 .21 .31 .09 .03 .19 .29 .09 .02 .18 .36 .12 .03 .21 .41 .12 .02 .27 .39 .13 .02 .24 ! .354 .11 .025 .215 -. - - II — I S ? i 721 721 722 723 724 727 728 729 731 735 19,24 248 266 268 288 512 513 Hard wheat meal Hard wheat meal Average Hard wheat meal Hard wheat meal Hard wheat meal Hard wheat meal Hard wheat meal Hard wheat meal Hard wheat meal Hard wheat meal Grand average hard wheat meals. Flour Flour ^ Flour Flour Flour Flour Flour Grand average flour 10.71 10.71 10.71 10.78 11.07 10.70 10.61 10.56 10.46 10.40 10.70 10.66 10.99 11.35 11.25 11.13 10.40 10.70 10.90 10.97 .223 .223 .223 .201 .224 .28 .159 .190 .212 .223 .179 .20 .235 .237 .214 .202 .245 .302 .266 .243 From these results it was decided to use the factor .15 per cent, as representing more nearly the gluten constituents, which pass into the salt solution in the treatment of soft wheat meals, than the one suggested by Teller, in the case of the so-called hard wheats. The other work indicates, however, that a somewhat higher factor should be used for the hard winter and durum wheats, and a still higher factor for flours. The markedly higher factor for flours undoubtedly is brought about from their finer condition. Even here, however, the factor appears to be lower than that suggested by Teller (.27), for in but one case out of the entire number did the figures rise as high as that. DISCUSSION Of ANALYSIS Of WHOLf WHfAT. Previous to analysis the samples were all held in the storeroom under uniform conditions for several weeks to secure greater uniformity in moisture condition. Each sample was freed from all foreign matter, such as weed seed, chaff, pieces of straw, dirt, etc., previous to being ground to a fine meal for analysis. The analysis of plump kernels only is recorded in these tables and in this respect the samples are strictly comparable. For the better comparison of results all the chemical data has been calculated to the basis of dry matter, but the percentage of moisture in the original is recorded in each case. It is of particular interest in the first place to compare the several varieties one with another. At the bottom of each table of varieties is given the average for each of the respective varieties. The averages are also set forth in a separate table (Table XIV). 354 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. I* Hi cm cm cq cm cm cm tA i-5 i-l thcmt-hcmcmcmcmcmcm i-i-rA ri«H!NH(MHHrtHHH' _ OilOJOlOCM CO CO CO t— 1 H t— I H o!2 OSIMtONCiOlMWHCJNOOTtfrHOHCDCO^N^NlNHCOOO "^C010COCOCOlO^CDiO»OlOCOCO«5lOCqCO-^CO'*»OlOCD«OiO i-icxD^co^oooioait^cocM^csocj^^coco^coooGit^cM loco^coco^Ttiioco-^^p^r'coco^T^t^^iotDiO'^TticocO'^" incoococ»cocccMco^c^^^»ocM?oc5t^oco cmc^i— i^r^t>.coTFO»ooicqt^aocNi— it>.-rt < i>-cooi | ^>ioc^o^T-j oo^c^oo^i-loo^odi>^idodot^i>:ai^^^cs^t^cdod«o'«o O TF OS 00 CM OS i-l O MON^^NlON^aOiOIMCOHNtD offiOMCoaswrHOiosintDTOiBooooiiMcoiMOioit^cosjTj; oc^^ioooTt^(>icqco^oii0^05aJi>^(^odt^cN^c>ii-5rHo6 Tf<»O^C^C0lO^C0lO^'*-<*l0iOrtT»f COGOiOOO^Ol OOOOCOOmiOWN'NtWOO^aiN.MNHWOS^NHJDN c^c^jc^cococoi-j^i-joiqixjoqocw^t^ococqc^co^rjHioio T^eo^ioco^^cococo^coccico^^ioio^jd^cficoeocici I CM CM !>; i-J OS Oi OS O; H CO O CM *0 CO icdoaiOiait>^oc^oio6c^oococNi-HT-Hc»oodt>^ j oq i>; cm o cm cm oq N(NNHHNW6O5HINO5C0NHHHHHh6^OJNNH NWOONlMCONrHNiMO co^*ococsia5ooco. 00 l-Hi-Hi-KM Wr- lt^ CM CM CO *0 t~~ < cm coco^t"*i •f ^rio<_ _ c^cmcncmcmcmcncmcmcncmcmcmcmc^csicmcmcmcmcmcmcmcmcoco 03 C3 ' ' ' ' ' ' ' ' ' ' ^ © CO I - -r LO Ol G- CO ^ OO CM l-O O O ® IO ■* ■* O0 H Oi lO lO N cc-^— ricn' ONcqnhthhhh i— ihcroix(N«o CO CM CO CO CM Bulletin 212] CALIFORNIA WHITE WHEATS. 355 i-H tH CM CM T-l rH C5 rti CM lO ^ ^H CO lO lO IO lO CO CO CO i-H CO OO lO CO OS TJ< "# -tf -«tf -* CO CO CO N»ONrHrHOOW §8; "* CO CO CC I>- Tf CO g§ eo cm co xo ^r co i OO t^ OO CO -^ OS t^ o IOf* WHO cm" cm o o cm cm co eocMcoio ihh -li-lt^CO I CO CM CMCMi-H ICMCO Si CO CO "^t 1 Tf Oi "^t 4 o co co co co co co co o I I ! I ! fcjo i i i i i C3 11111 Sh i i i i i 8lO O *0 i-H CO Ol OO CXN mm:: i-i co cm 356 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. i o M w I o CM CM CM CM CM CM 'iOCDailr^05000i0500CO'X)COC^OOOOOOC»COlO 5 § k o fl « d 8 lS Ss£2 TjilOlOiOlOTtiCOlO'^iO- NIOH 03H»OlO(N(MHGOm?DOOfOOC0035DOU3(MCOOOCD(NH'>tCi oqcocoooTjjoocqco»OT-(?DT-(i^'<^oqoic>OiC500sco?D'«^osi--t :gS ojooaeorHO>NoooojHOiNHo»Mc>iO>oo>05 0sa«o «COCO0Q(N(NrH(MTH t- £ a> o COON t^-^CO (NCOO(MCOHOOOW li- 00 rt< ^ ZO as 7-1 •* i-H CM 100 1 CM CM "<3< CM CO CO r-l CM ^ CO 1 CO 1 CO icMcococo^^ioioio^^cococoi>-i>-t^i>-r^oooooo (^O^CMCMCMCMCMCMCMCMCMCMCMCMCMCMC^CNCNICMCMCMCMCMCNCM California number of sample. CM Ol r-( fig SO I - CC Ol I - O — OC 1 «P CO' Ol OC -H 00 H H -r — co -r< 00 CM w (O co c c 1 -r 1 - x c 1 - ci 'r -r n x 1 c rn c. :c x - ri x co 00 co rP -r CO — SC — — CO CO O ICO CO CO CO — 0-1 CM Bulletin 212] CALIFORNIA WHITE WHEATS. 357 tH i-H tH i-l i-l H i-H N CO^COCO"'*t^-r , iC>-<*CO'*CO''3<*OCOTt l CO oa>ai^ococo«30i-ioooot^coio05cx)oo«o^cO'rHt^idoocDt^o6 T} tp cm in cm co <^^c6THeo^ icmoo o CO CO CM CO i-H CM CO CO CO ICMCM I CM tH CO COMOOCCaONCtOCOWOOHNCN^OJW ?o asasasasasoooi-HCMCMcoeococo'-tiiccot^ oo C^0l0 oi co oi nr: co co cm oi co re 358 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. w — 1 1 S gj PUi X H PQ COO0t"~CNI>«DNOOONNNCOOt>NrHNOI>tDt>NtO «|2 III is & fc - c ^(NOMNOOOOmmoOHOOMCOCQ^lOCOOOH C0(NOCD'*0:rH^0005'*OTt<00C0^Cn(M00l0r^l 81 t^io-^^-^r^co^^^ 10 co-<^co->*i?D'^'* 1^0000-* OffiHH icwqin co-^uico rt<< lliliilliilJlTlliiiiiilii ^KHOroHlONHN-^OOOtDOOHtNOlOOSOOCCCO^OOOOOtOlOm io^^cococo^^^co^io^cococo^* , c^co-<#'^"'tf | iDco^r | *oiO'<*'*-<^ 81 CO«OCOi-ir^C^l^COC©COC©COI>-OCOOOlOC^COt^CDt--C^OOOOCOCOl>-CO s ICOIOIO^CO"* 1 "*-*! cococoi-HCMCMaicio^-iaiooT-io eo>CMeOT^coiococ^^u3co^co-lOOt^'rHCOTtiCO»0-<#CD oqrHqoqwffiNq^coiroco^icm©THrHOsrHqioN5qqiO'^HN(ro ^oo^i>eo^c<5crirHiHc<>©oo^co^ocHc»oo^i>^o6oo^aicx5o6o6o l^^c©o^©cNt^ocDCM o IO(N'ddTHWrHHrHNr4oi(NrH- t— r- OO Ol C5 t-h CO CO CM CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO -* ^ lO CO ' ' CS ' ' o !!!!!!! to i i i OS 1 l l 1 1 1 1 1 ;_ ' ' O 360 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. $ I C a - ■3 ' T) S I 2 (Mr-! 1 lOlO(NTH(M(N rirlriririHHHrlNNHHrtWrlN cm idiq co COr-5 co c^ co t~~ co co c>- 1>- r^ oo co io t^ WiMWHtOHCOONHOONlNMCOlOH 0 "^ tF "* tji CM cq ""*• B'Sfi rlNH rH CO ^ t^ CO iO (M CO CO l>- »0 rH TJH -*f g -2 -5 CMrHOscqcooqcqiDr-jc^cqoqiq^^c^fM oq 5 *? IC^OOC^c6(ModrHodoQrHt>Ia5rHTjHt>i!c6(M IO £ ° G r' : ! Tt" CO ; ■^ os i-^ o od i> os od os oo io os od as cm t>^ oo os (005HrHH->*iNOO Tt< lO(ONN0001050:a510WNNN1» r*- KMr-lrHCM CM rH tH rH CM r-l rH r , rT 1 ? HO TJH t-- CM IO OS iO -^ -^ -^ IO "tf" t^ CO ^ CO CO CM CM -**i CO O CM OS od t>^ od od os os co -^ ■"*! -* co io S3; -* co co co io -*> tf iO OSOSO( O 00 OS OS r-i r-i HOINOIHH r-( HO 00 CO COOtH CM rH CO CO C^ OS CM "># CM (M CM CM CO CO CUD C3 I CO l^lO-'f l^OS > t oo -r h tN ^ ; co -* *s ' Bulletin 212] CALIFORNIA WHITE WHEATS. 361 < , H C^l t Ol W OOOOjO CM* CM CM -rH CM o CM 2 la 4 CD©OHOO c^ocqcqoq 1-5 cm th t-h tA 8 a 3 O Glladin- glutenin ratio. 10»0 kO lO lO io 3 Total per cent of wheat. cotocooco HH(OOSN Oft CM CO 53 3 3 Per cent of total protein. -*' cd to id cm ^ ''T* "^ ^t* ^f CM id Per cent of wheat. C5 CO CO CM CM COCOCM^ CO ^H ^H '^ ^" l Tj^ <* CO a •a 3 Per cent of total protein. Gliadin number. hOOO^O oq^r> a - Number kernels in 10 grams. i 00 00 (M ^ CO CM CM COCOCM • 00 Ci CM Number of samples repre- sented. CMCOCM t^lO rftMlOrH OS 4— b212 < so 362 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. The first thing which is apparent from this table of averages is the much larger moisture content for these wheats than is usually stated for wheats. In fact the variety tables show quite a range in moisture, all the way from a maximum of 14.17 in No. 391 to 9.18 per cent, in No. 196, with a general average for all samples of 12.11 per cent. This is a considerably higher figure than it was expected to find, especially as the analyses for the most part were made during the dry season. Richardson, as an average of 310 samples of American grown wheats, gives 10.50, and in these samples there is also a wide difference between individual samples, viz., from 7.1 per cent, to 14 per cent. In the case of results here stated wherever there seemed to be any question, the work was checked by a duplicate determination. This generally high moisture content of the samples may perhaps be partially explained from the fact that the laboratory is situated comparatively rear the bay and the atmosphere is usually quite moisture-laden even during the summer. That grain absorbs moisture from the air very readily, has been shown by experiments carried on at this Station in bringing grain from the interior sections of the State where the atmos- phere is very dry to the coast region. Undoubtedly this fact has had much to do with producing the condition here shown. It is claimed that the moisture that wheat will thus absorb during a voyage from San Francisco to Liverpool will sometimes increase its weight enough to pay the entire cost of freight ( ? ) . In the experiments above indicated it was shown by Dr. Hilgard that wheat from the inland portions of the State might increase as much as 25 per cent, by absorp- tion of moisture, while a gain of 5 to 15 per cent, may be looked for with absolute certainty. A difference of 9 per cent, was observed in twenty- four hours. It is barely possible that this increased moisture content may have some chemical influence upon the quality of the gluten which is a matter that will be again touched upon. As to protein content the varieties stand in the following order, Propo, Bluestem, Australian, Sonora, and Little Club. This is the more noteworthy since it is in the same order that the miller would probably class these wheats. Thus it seems that a determination of the total protein, or what amounts to the same thing, the total nitrogen, would serve to classify the varieties in a very general manner as to adaptability for milling, aside from their physical characteristics. In 310 analyses of American wheats compiled to 1890, the protein content (Nx6.25) varied from 8.1 to 17.2, with an average of 11.9 per cent, in samples carrying 10.5 per cent, average moisture content, which calculated to the same basis of dry matter and factor as presented in Bulletin 212] CALIFORNIA WHITE wheat-. 363 these wheats would correspond to an average of 12.08 per cent. The analyses here shown give an average protein content of the white wheats of 9.95 per cent, in the dry matter, or about 2 per cent, lower than the general average of the common wheats of the country. The gliadin follows the same order as the total protein. The glutenin. however, does not follow the reverse order, without a variation in the order of arrangement in the wheats, owing to a variation of the non- gluten proteids. It w^ill be seen that in the matter of non-gluten proteids Bluestem exceeds the others quite materially. The effect of this is to reduce the glutenin, and thus to displace this variety from the order shown by the total protein. The gluten, chemically determined, runs in the same direction as the total protein, which would necessarily follow unless the non-gluten proteids were unduly large and the differ- ence in gluten between any two varieties very small. Another thing which appears from the table is that as between varie- ties neither the total protein nor the gliadin bear any definite relation to the size of the kernels. Turning attention to the proportion of total protein of wheats existing in the form of gluten, as determined chemically, w T e find as follows : Bluestem 80.2 per cent. White Australian 82.9 per cent. Little Club 81.9 per cent. Sonora 81.4 per cent. Propo 82.3 per cent. Average S.15 per cent. There is shown to be very little difference in the ash content of the varieties. It is seen that the ash does not follow the size of the kernel closely, as it does in the north central states, nor is there as large a per- centage. In a general way it follows within the type, but the partic- ular character of the wheat not within the same type breaks the order in this regard. Thus a Sonora sample, with its thin bran, which part contains the larger portion of ash, carries a considerably lower per cent than does a Bluestem sample with the same size grains. As compared with the average ash content of the United States wheats, the California grown varieties are relatively low. It is the custom to consider both the gliadin-glutenin ratio and the gliadin number in connection with flours rather than the whole wheats, because the operation of milling changes the relation of the ingredients to a greater or less extent, but since it is highly desirable for us to make certain comparisons of grain before more than a very few plants can be had, and since, further, it was desired to ascertain what was the result 364 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. of milling upon this ratio in the case of the common white wheats, these data are also calculated for the whole berry, as well as for the flour later. To either the miller or baker it will have its greatest significance in con- nection with the flour. Since the larger part of the gliadin is in the endosperm of the grain the milling will of course raise the gliadin number of the flour above that of the whole wheat. While Table XIV shows an appreciable difference between one variety and another, within the same variety there is even a greater difference between individual samples than between the several varieties, as will be seen by referring to the minimum, maximum, and average results, as subjoined : Maximum protein. Minimum protein. Average protein. Bluestem _ _ 14.40 13.42 13.53 15.80 11.94 7.15 6.92 7.38 7.59 8.97 10.18 White Australian __ 9.89 Little Club Sonora _ — 9.35 9.71 Propo _ 10.64 Australian, for instance, shows a range of from 6.92 per cent, of total protein in the dry matter of No. 232 to 13.42 per cent, in No. 26. Very generally speaking the gliadin seems to rise and fall with the total protein, but there seems to be no definite or absolute ratio between the two. This is also in accord with most other results that have been published. There are exceptions even to this statement that the gliadin rises and falls with the total protein in whole wheat ; as witness, samples 326 and 312, the former carrying 10.48 per cent, total protein and 2.91 per cent, gliadin, and the latter showing but 7.97 per cent, total protein but rising in gliadin content to 3.77 per cent. Still, while individual instances of this kind do occur, it may be said that in general the gliadin does follow the trend of the total protein but does not bear any definite ratio to it. The same statements hold concerning the other varieties, although Biuestem appears to run more even than White Australian. Little Club, while generally running lower in protein, has certain lots which rank very high in this group of compounds, as for instance Nos. 459, 444, 6, 27, and 29, which suggests that it might be possible to fix these clxir act eristics to a certain extent at least, even in this variety. The Bulletin 212] CALIFORNIA WHITE wheats. 365 unreliability of this variety in its present condition, however, has given it a very low standing among millers. These cases of unusually high protein content are also apparent in the other varieties. The underlying causes of such wide variation are not apparent as yet. One would at first, perhaps, assume that it was due to soil conditions of the locality, but an examination of the record accompanying each sample does not reveal anything definite in this direction. In this connection it is interesting to record a series of analyses of grain taken from the entire product of individual plants. Each of the samples used for the analyses stated below were made up by using the grain from one half of each head of an individual plant. Even here, in the case of the three varieties cited, there will be noted the great variation between individual plants, and these were grown under exactly the same climate and as near as possible upon the same char- acter of soil. The variation in individual plants of Australian ranges from a minimum of 9.06 to 15.31 per cent, total protein, or a variation of 6.25 per cent, within 25 plants, and the range in Little Club is even greater, being from 7.12 to 16.22. Such a variation as here appears among individual plants, grown under the same conditions of soil and climate, would seem to cast grave doubt as to the effect of climate or soil upon the composition of the grain, except in a very general manner, and to throw the ultimate causes of difference within the plant itself. 366 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. O 35 ® sg O O £ o c. — ooowooaoTHn^coccOrHO (•<•*»(•(*. ."/"* /*n 1 — >-ni nTi i i^> rv*i r — - Nt^OMOOOJOJNOOHNOIN'NKCCMXN X ■gas - = = - Z & «j <| J o> . Oh i a & S 8 "tf O O 00 CO 00 Oi0000 050iWrH-*5plOOOOO ^L:0 5Cl^N050riHHO)T , CCXO l NCO t- ,-H — r-i y-i i-l t-i CM CM CI CM CM -OSSD-^ lO HHHOrtHNrtOOrtOrtNrtQrlOOO ro co co cocoeoeococooocococococococococo co l — t — r — t> l^ L-~ l^ l^ t^ l^ l^ t> l^ L^ l^ t-- l>- l^ t>- L~- "X - e a > O ~ 'S n 555 £ A Pm b z ■a c X w M 8 «> c > Ph a _ H H G o XT. « . ffl 3 at S rt « 02 Z T (j 3 Eh £ -- C < - 3 -1 11 § n z < F- ti O a - a_ d " O c3 "S Z S5 £ Ph c. > c = cg| -/. S *?£ in -~ '- o !> d - X fc , r H rt a|s« l— ; - - 1 ~ ^ ^ i *** — o a w M a s — 2 -a Q S « rt Gi ^1 CI X C 'I* LC -* N N C OJ CD rH 00 CX3 X) io a LO -1< (M l-O m QO CO^COCX3^CXDO^C^^lOT^OCO^^C^r>.r>.COO^CMT^Ot>. oi^C-lT-I^T^^T-JcMCM^i-Ii-icMCMCMT^CMT^T^^CMT-Si-Hi-H XCCOlCCOOOCDWMOt^COXCD^ooacOOCDOOCD OOCfMC-fOSiHOOlOCOO^rHCMXX^NOCOCSXH (COCMOl-OlO co^Oic^>OL6idKicdxdidcctdcto!idido6cx3cx)c^ TO CT. ^ C-: X X ^C C: -f O rH CN LO N a CC CD C) N CD TO CD CD C1N O y-i CM CM CI CM TO TO ^ K2 iO lC ic i_C iOCCNMXCROOOM l-Cj i-IT^nr.THHHHrtHHrtHT-IHHi-lT-IHHCN(N(N(NCN TOCC^OCC^CC^a:Ot^TOCXjCCCl-^--t l 'Mt^lOlO»-OCO'-^CMi-w HHNnOrtrlHNHNQONi-tCNHOOHCNOOOO X X X X X X X X X X X X X X X X X X X X X X X X X C.-riCN-^UCCO^CNOOOOXOi^Ol' I O CM -r-i CO l^ 0O t-I "* rf C C - Tl X ~ . TO 'MCDa-tNCDf iCNlOHHOCDTfCl -Hr^-rt^cocciowNTOcC'Xcici^^xojffico^T-tinKSco NCDCCC1C'MNCO'*CIXXXC^ , C1 < 10 050>HOX(N'* thNMi-HMM CM CJ CI CI H H i-H • t-H CM CM CM i-l tH i-.cci-'ct^oi^i^cooi-i^-r'-^r^-^^tico'TOiocort'ajoocM -rTOLCTiCXffiCftNMOCOOlOCSNOTOOCqiONHXN c !^^^^!^,"NrH^Tt;qqqxcNrHioqxxqxcoco dddr-ir^cidHo:' of Bulletin 212] CALIFORNIA WHITE WHEATS. 367 The effect of seasonal differences in the grain would require a series of analyses covering a longer period than is here represented, but it is generally regarded that these do have a greater or less effect in causing a fluctuation of the entire mass for any one season as compared with another. Below are presented averages of the previously stated analyses separated according to the years in which they were grown. TABLE XVI.— AVERAGE COMPOSITION AS AFFECTED BY SEASON. Australian. Club. Bluestem. 1904. 1905. 1904. 1905. 1904 1905. Number kernels in 10 grams Relative hardness of kernel Moisture Total protein Gliadin Glutenin Gluten Non-gluten protein Carbohydrates and fat Ash 287 286 11.71 10.38 3.95 4.58 8.53 1.85 87.42 2.00 283 342 327 212 12.42 11.86 297 281 222 249 12.13 11.81 8.90 3.19 4.08 7.27 1.63 9.43 3.59 3.96 7.55 1.88 9.36 3.13 4.71 7.84 1.52 10.47 4.05 4.23 8.28 2.18 89.08 ■■ 88.58 2.02 1.99 58.72 87.47 1.92 2.06 280 328 11.62 9.12 3.00 4.70 7.70 1.41 88.93 1.95 It appears from these averages that the season of 1904 had a tendency to produce a smaller kernel, and one of somewhat higher total protein than did the season of 1905, and that this was also true so far as the gliadin was concerned, but that it does not hold with reference to true gluten. It is undoubtedly true that should the season be such as to seriously arrest the development of the grain, and thus produce a pinched kernel, then it results in a markedly higher gluten as well as gliadin content. This is shown in the analyses of a considerable number (82) of pinched wheat samples grown in the same years as the samples given above, the results of which analyses are stated in Table XVII. TABLE XVII. -SHOWING AVERAGE COMPOSITION OF PINCHED WHITE WHEATS. Chemical analysis. Calculated to dry matter. are. r3 Club (46) Australian (17) Bluestem (13) . Sonora (6) Average (82) _. 405 341 366 442 388 12.28 11.59 12.18 12.12 12.04 9.79 11.78 10.60 9.62 10.45 3.88 4.83 3.85 3.68 4.06 39.63 41.00 35.27 38.23 38.5 4.33 44.23 8.21 1.56 4.95 42.02 9.78 2.00 4.96 47.84 8.81 1.97 3.76 39.08 7.44 2.18 4.50 43.8 8.56 1.89 2.11 2.12 2.02 O 08 368 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. MILLING TESTS. The flour used in making our ordinary bread is the white portion called the endosperm separated from the remainder of the kernel. The whole aim of the miller is to get as large a portion of this white material free from the dust hairs and small particles of bran (cuticle, episperm, tegumen ( ?) and embryonic membrane taken together), and other unde- sirable products which impair the color, odor or quality of the flour. To-day there are probably more differences in mills and methods of milling than ever. To mill all the different kinds of wheat and mill them to the best advantage into the different products for which each wheat is best adapted, slightly different processes must be employed, and millers do not agree as to the best method for obtaining certain ends, nor do they seem to think it urgent that a standard by which they mill should be adopted. Some agitation has been started, however, and it is hoped that some satisfactory standard may be found. As the sit- uation now stands, every miller makes his own standard and determines the quality of his brand, and to the purchaser the name is meaningless. As stated above, the aim of the miller is to obtain the largest possible yield of clear white flour. This is accomplished by screening, scouring, fanning, and washing the wheat, as may be deemed necessary, before grinding it. Washing is very necessary with California grown wheats since they are not as clean as eastern grown ones. Then, too, the native wheat is harvested and immediately bagged, in which condition it stays until it reaches the mill. Not only do they contain the dry dust from the dry summer fields, but also smut and bunt as well as a goodly sup- ply of grasshopper segments ; and the aroma, after two, three or more months, penetrates the seed to such an extent that it is noticeable for some time after it is emptied from the bags. Eastern dealers in grain rarely, if ever, find this condition, but instead have "musty grain" which is caused by dampness. Aeration greatly improves musty wheats, and the same process would improve the above-stated condition in California. Having cleaned the wheat properly, it is put through a series of two to six corrugated rolls and five to eight sets of smooth rolls, the number of each varying with the process used. Between each set of rolls the middlings are sized and separated into a varying number of streams, so that every set of rolls furnishes a stream to every following set as well as some portion of finished product. The total number of streams pro- duced depends entirely upon the method of sifting and bolting. Bulletin 212] CALIFORNIA WHITE WHEATS. 369 The corrugated rolls are primarily for loosening dust, hairs, and the outer portion of bran layer. No attempt is made at grinding, but only at cracking. In this process some of the particles of flour are lost, and this, with the dust and other loose particles, constitutes the low-grade flours. The amounts lost in this operation depend upon the condition and quality of wheat and also upon the skill of the miller. After the removal of the low-grade flour and the bran portion, the remainder of the process is the purification and reduction of the mid- dlings into the higher grades of flour. Since the portion near the bran has a higher per cent, of gluten than the center of the grain, it is obvious that, for a flour with high gluten content, the milling must be as complete as possible and since the central portion is the first to be reduced because it is softer, and unprotected after the grain is split, the flour from the first breaks contains less gluten than that from later reductions. While the product from jthe last rolls is richest in total protein, it is also contaminated with particles of bran and a small amount of germ, which lower the color and quality of the flour so it can not be included in the patent grades, but rather in the clear or bakers' grade. Method Pursued. — The preparation of the flour was made on a small experimental mill with two sets of rolls, one with medium corrugations and the other smooth. The sifting was done in an attached frame carry- ing three separate bolting cloths or wire sieves, as was necessary. This frame was completely enclosed, and the pan for receiving the flour was boxed under the platform, the flour being conducted from the shaker through an opening in the platform into the pan by a canvas stocking so as to reduce the loss from dusting to a minimum. 370 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. BRAN, SHORTS, AND FLOUR. The terms flour, shorts, and bran are rather flexible terms, and hardly capable of exact definition, and for this reason many regard the stated yield of flour as having relatively small value, yet, where the tests are made with some degree of uniformity, the mill not being forced, and only that portion of the possible flour being put into the "straight" product, which can be so done without reducing the color standard, it should convey a meaning of relative value. It is, of course, perfectly easy to make seventy per cent, or more of straight flour from even the lowest grades of wheat, provided the term be employed in a sufficiently broad sense to include all that can be obtained from the wheat, and a little more grinding will always bring a little more of the bran into the shorts. For the above reasons the proportions of products obtained by different operators may seem to vary quite widely, and the same varia- tion occurs in the commercial products, particularly in what is com- monly called "patent flour," which is largely dependent upon the flex- ibility of the manufacturer's conscience. Fig. 14. — Showing small grain scourer used. in these experiments. In these experiments, before grinding, the samples were cleaned as thoroughly as possible by screening and passing them through a small sized "Invincible" scourer designed to remove all dust particles and the brush upon the ends of the kernels. The varieties all being "soft" wheat, it was not deemed necessary to "temper" them with water, as is frequently done. Ordinarily, the grain was subjected to two reduc- tions upon the corrugated rolls, although in a few cases a third was deemed necessary. The middlings were usually reduced in three oper- ationSj more were required in a few instances. Flour. Since only a "straight grade" flour could be made, the material was all passed through a No. 10 bolting silk, and care was taken to include in this all the material which seemed by its color to be fit for lli«' making of fair quality of bread. To unify the product it Bulletin 212' CALIFORNIA WHITE WHEATS. 371 was now passed through a No. 11 bolting silk, and all that passed this silk was termed flour. The part retained on this gauze, when judged to be clean, was termed "low grade." The flour from the first break was not dark enough to be necessarily put into the low grade class. Bran.— The portion of the chop retained on a 2 mm. mesh wire sieve was termed "bran." Shorts. — The "shorts" was separated from the middlings by a No. 50 and a No. 70 grit gauze, the former being used in the first and the latter in the last two separations. In each case a kilogram was taken as the basis for milling. The yield of mill products is stated in the subjoined table, which also states the bushel weight, the condition of the berry, and the relative ' ' commercial Fig. 15. — Small Allis-Chalmers mill used in these experiments. grading." which latter was obtained by taking the average of the grades placed upon the samples by the "official" grain inspector of the Merchants' Exchange and that of one of the well known millers of the State, on the basis of the terms "choice milling," "good milling." "fair milling." and "poor milling," and allowing a difference between each term of 2.5 points, choice milling being rated as 100. The loss due to dusting and arising from transfers of material ranging from zero to three per cent., is likely to belong mostly to the flour and for the sake of uniformity has been so returned ( ?). 372 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. Not much difference could be noticed in the reduction of the various samples. The relative hardness of some could easily be recognized, especially if two samples with extremes of hardness were ground one after the other. There was an appreciable difference in the bolting of the same. Some of the Club samples, as millers generally recognize, required more time to obtain the same separation, but some also bolted as readily as either Bluestem or Australian. TABLE XVIII. — YIELD OF MILL PRODUCTS. White Australian. Bushel weight, pounds. 63.0 62.5 62.5 61.0 60.5 61.0 60.5 61.0 59.5 62.0 58.9 58.0 57.5 59.0 63.0 56.1 60.0 Condil.,.i of berry. Plump Plump Plump Plump SI. pinched Plump Plump Plump Plump Plump Plump 59.5 i Plump 59.5 Plump 56.1 ! Pinched 58.0 | Plump Plump Pinched Plump Maximum Minimum Average _ Relative grading. 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 98.7 98.7 97.5 97.5 97.5 96.7 96.7 96.7 92.5 100.0 92.5 0.0 Bran, per cent. 18.0 18.0 16.0 16.5 16.5 16.5 15.5 17.0 17.0 18.0 15.5 16.0 16.0 15.5 16.0 18.0 16.5 16.0 18.0 15.5 16.6 Shorts, per cent. 11.5 9.5 14.0 13.5 12.9 11.0 12.0 12.5 12.5 12.0 12.5 13.0 13.5 16.5 14.5 11.5 13.5 13.5 16.5 9.5 12.8 Flour. Straight. grade. 69.0 2.0 70.5 2.0 68.0 2.0 68.0 2.0 68.7 1.9 70.0 2.0 h 70.5 2.0 68.5 2.0 69.0 1.5 1 68.0 2.0 70.0 2.0 68.5 2.5 68.5 2.0 66.0 2.0 67.5 2.0 68.5 2.0 68.5 1.5 68.0 2.0 70.5 2.5 66.0 1.5 68.7 1.9 .0 .0 2.0 .8 2.0 .5 1.0 .0 1.5 1.0 .5 .5 1.0 1.0 1.0 1.0 .0 2.0 .0 .9 Washington BluestPin. 62.0 61.0 60.0 60.7 59.0 60.0 59.0 59.3 59.5 60.0 59.5 58.5 58.8 58.0 58.0 57.2 56.5 62.0 56.5 59.3 Plump Plump Plump Plump SI. pinched Pinched ___ SI. pinched Plump ____ SI. pinched SI. pinched SI. pinched Plump Plump M. pinched SI. pinched M. pinched Plump Maximum _ Minimum _ Average __ 100.0 16.5 10.5 70.5 100.0 17.0 12.0 69.0 100.0 16.0 12.0 70.5 98.7 19.0 9.0 70.0 98.7 16.5 13.0 68.5 98.7 15.5 13.5 69.0 98.7 15.5 14.0 67.5 98.7 16.0 14.5 67.5 98.7 17.0 11.5 69.5 97.5 16.0 12.0 70.0 97.5 15.0 13.0 70.0 97.5 16.5 12.5 69.0 96.7 18.0 13.0 66.5 95.0 17.5 13.5 67.0 93.7 19.0 15.0 64.0 90.0 17.0 14.0 67.0 93.7 18.0 13.0 67.0 100.0 19.0 14.5 70.5 90.0 15.0 9.0 64.0 0.0 16.8 12.7 68.5 2.5 2.0 1.5 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.5 2.0 2.0 2.0 2.0 2.5 1.5 2.0 2.5 3.0 .5 .0 .5 .5 .5 3.5 .5 2.0 .0 .5 1.5 .5 2.0 2.0 1.0 3.5 .0 1.3 Bulletin 212] CALIFORNIA WHITE WHEATS. Little Club. 373 5s Bushel weight, pounds. Condition of berry. . Relative grading. Bran, per cent. Shorts, per cent. Straight. grade. 163 60.5 233 61.7 266 60.0 253 59.0 28a 57.5 313 58.0 179 60.2 51a 58.5 185 60.0 317 59.4 277 57.5 305 59.5 169 60.0 50a 58.5 315 59.0 270 54.5 247 54.0 290 57.8 316 55.0 SI. pinched Pinched ___ Plump Plump Plump SI. pinched SI. pinched SI. pinched SI. pinched Plump Plump Plump M. pinched Plump Plump Pinched ___ SI. pinched SI. pinched Pinched ___ 97.5 15.0 14.5 68.0 2.0 97.5 16.5 14.0 67.5 2.0 96.7 16.5 12.0 69.5 2.0 96.7 18.0 12.5 67.5 2.0 96.7 14.5 13.5 70.5 1.5 95.0 17.0 12.0 69.0 2.0 95.0 17.0 14.5 66.5 2.0 95.0 16.0 14.0 68.5 1.5 93.7 16.0 15.0 66.5 2.5 93.7 16.5 12.0 70.0 1.5 93.7 15.0 14.5 67.5 3.0 93.7 17.0 13.0 68.0 2.0 93.7 18.0 14.0 66.5 1.5 93.7 16.0 12.5 69.5 2.0 92.5 17.0 13.0 68.0 2.0 92.3 18.0 12.0 69.0 1.5 92.5 19.0 14.0 65.5 1.5 92.5 17.5 14.0 67.0 1.5 90.0 17.0 11.5 69.5 2.0 2.5 1.5 .0 .0 1.5 .5 2.5 1.0 .5 1.0 1.5 .5 .0 .0 .5 1.0 .0 2.5 .5 Sonora. 481 254 74 249 257 248 66.0 63.7 63.0 62.8 58.7 59.0 Plump Plump Plump Plump Plump SI. pinched 100.0 11.0 20.0 66.0 3.0 98.7 16.0 13.0 69.0 2.0 97.5 9.0 20.5 68.5 2.0 97.5 15.5 14.0 68.5 2.0 96.2 16.0 16.5 65.0 2.5 85.0 19.0 14.0 65.0 2.0 2.0 1.0 2.5 1.5 2.5 1.0 Propo. 468 225 226 62.8 57.0 53.0 Plump 100.0 SI. pinched 95.0 Pinched I 90.0 16.0 11.0 15.5 12.5 69.0 2.5 23.0 64.0 2.0 20.0 61.5 3.0 2.5 .5 1.5 Examining the columns recording the flour yield, there appears but small difference in the flour yielding power o'f the three principal wheats, with the White Australian in the lead, the average yield being 68.7 per cent, for the White Australian, 68.5 per cent, for the Bluestem, 68.2 per cent, for the Club, and 67.0 per cent, for the small-grained Sonora. The greatest difference in flour yield is seen to be 8 per cent. This occurs between samples No. 206, which yielded only 62 per cent, and several samples each yielding 70 per cent. Number 206 is a fairly plump sample, but the kernels are not dense and the weight per bushel is only 58 pounds, while those samples which yielded 70 per cent, flour averaged about 61 pounds per bushel. It does not follow, however, as may be inferred, that those wheats weighing heaviest invariably yield the largest amount of flour. In the yields of bran and shorts, the average amount obtained is about 30 per cent, of the whole wheat. The Sonora wheat, on account 374 university of California — experiment station. of its smaller size, giving a larger proportion of surface, yields a larger percentage amount of these constituents. The bran coat is actually thinner on this type than on the other three, so that if the kernels were as large as those or Bluestem it would undoubtedly give larger flour yields. THE BAKING VALUE OF A FLOUR. In deciding upon the baking value of a flour there are three points which demand particular consideration, viz., the color, the gluten con- tent, and the strength, or absorption capacity, all of which points must be satisfactory in a flour of the best quality for baking. A chemical analysis alone of a flour tells very little of direct value to a baker, as it does not necessarily indicate the character of the loaf which that flour will produce, but if the baker knows the gluten content, the strength, and the color, he can form a fairly accurate idea as to how the flour will act in baking. In addition to the above, there are certain other characteristics which act as aids in enabling one to have a better under- standing of a flour. In general, it may be said that there are two classes of flours as to their effect upon the touch. One type may be described as granular, hard, or lively. It may be poured from one vessel to another with comparative ease, and is somewhat suggestive of an extremely fine sand. The other type is usually referred to in con- tradistinction as soft, velvety, or smooth. It is this latter type that is obtained from the milling of the soft white wheats here under discus- sion. Relatively speaking, the latter type is considered weaker than the former in bread value, but better adapted to pastry, biscuits, etc. This, however, is not without frequent exception, as very often soft wheat flours may be found to have excellent baking value even when made without blending, as will be seen in the tabulation later. Color. — One of the most important characteristics of a good flour is its color. While mere color is of no direct benefit, it is a property much desired, and one by which the relative merits of flours are judged to a large extent by millers, brokers, and housewives alike. The color depends largely upon the mechanical composition of the flour. The poorer the process of milling the larger the amount of foreign particles which give a darker color. High moisture usually has a darkening effect. The color of the gluten is also effective in varying the color of the flour. California wheat produces a very white flour on account of it being very starchy and having a small amount of gluten, which is not so highly colored as in other wheat flours. They have little of that creamy color so characteristic of eastern flours. There are some, however, that are quite as yellow, and in the Sonora flours examined some had con- siderably more yellow tint than the eastern flour used for a standard of comparison. Bulletin 212] California white wheats. 375 In the washed glutens the color is more noticeably variable than in the flour. For the most part these glutens are blue gray. Occasionally there is a creamy one ; generally the creamy-colored flour gives a creamy gluten, but a creamy-colored gluten need not follow from a creamy flour. The Sonoras invariably yielded creamy glutens. The whitest flours do not necessarily produce the whitest loaves. In no case does the color of the bread hold the same relative position in the loaves as the color of the flour. In a general way, all tinted flours are a little darker rela- tively when baked, as their color value does not increase. The yellow- tinted flours appear to change their relative value more markedly. The color, however, has no real relation to the baking or nutritive value, and, as may be inferred from what has been said, is not a very reliable guide as to the color of the resulting loaf, although it generally holds that gray flour produces a dirty-colored loaf, and that, inasmuch as a yellow flour usually indicates a high gluten content, they usually show less loss in the oven and therefore have a better bread value, and do not necessarily produce a darker loaf. The matter of color, while it certainly does affect the commercial value of a flour, is a decidedly sentimental factor. It is also noticed that those flours which enhance their color value in the process of bak- ing show a slightly lower loss in the oven. A high color value is quite commonly associated with low gluten and low strength. The amount and quality of gluten also have their effect on the color of the bread. Those flours with a low quality of gluten, and especially if the gluten is rather dark, produce bread that appears uneven in color. This is due to the breaking and massing of the gluten, thereby making uniform distribution of the gases impossible, and preventing uniformity in color. In carrying this comparison to the dough, it is seen that the same relation invariably holds. The color value of flours from this class of wheats is high both in the dough and in the flour. The relative color value between the flour and the dough made from it is not expressed in the table, because of the lack of a satisfactory method of definite state- ment of this factor, but the dough is always relatively darker than the flour from which it is made. As to the relative color of the breads, it is the same as in the dough and flour with the exception that the yellow Sonora flour has baked whiter than the Club flour, which is probably another reason why millers do not like Club wheats. On account of lack of time and the somewhat mixed conditions of these commercial wheats, no attempt was made to subject them all to either milling or baking tests, but instead selections were made to rep- resent as wide a range of condition as possible. Owing then to the com- 376 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. paratively small number of samples baked, no attempt will be made to formulate definite statements to be applied to the several varieties when the samples are pure. This must come from a later study now in progress in which the varieties are of known purity. An inspection of the table, however, shows a number of interesting points which will next be discussed. Inasmuch as the calculation to dry matter would not change the rela- tive position of the samples in any case, the results are stated on the basis of the original condition of the material. Moisture. — As in the case of wheat, the moisture content of flour is largely determined by the atmospheric conditions under which it is stored. Around the bay sections of the State, flours would show a much larger percentage of moisture than would those of the same grade in the interior, and likewise their absorption capacity, or strength, would be somewhat lessened, provided the gluten content remains the same. From a commercial standpoint the question of moisture is as important in the case of flour as in that of wheats mentioned earlier in this bulle- tin. A large profit it undoubtedly brought to dealers through the influ- ence of this factor alone. As might be expected, the moisture content of the flour is invariably higher than that of its corresponding wheat. The maximum moisture content shown in any of these flours was 14.13 per cent, and the minimum 11.32 per cent., with a general aver- age of 13.57 per cent, for all the flours examined. These are very high figures as compared with those from Canadian flours, which are reported as carrying from 9 to 10 per cent, and Minnesota flours which carry about 12 per cent. In no case did the moisture content fall as low as those indicated for the Canadian flours, and in three instances it rose above 14 per cent. To a certain extent this difference in moisture will account for the difference in the amount of bread that can be made from flours produced in those sections as compared with the Coast flours. This same will undoubtedly apply to flours in the interior of the State as compared with those in the coast section. For the bread maker this is quite an important matter, since, other things being equal, the drier the flour the greater the weight of bread that can be made from it. Xitrogenous Compounds. — It was observed in the case of wheat that the total per cent, of proteids was low. The average protein content of the wheat milled was 8.57 per cent, and the average of the flours milled from them was 7.03 per cent: or about 82 per cent, of the total protein of the wheat passed into the flour. Quite generally the amount of proteids found in flour depends upon the amount contained in the wheat, though it does not follow in everv case that the wheat with the Bulletin 212] CALIFORNIA WHITE WHEATS. 377 highest proteid content yields a flour with the highest percentage of proteids. Total Protein. — In the matter of total protein the flours take the fol- lowing rank: Propo, 7.83 per cent.; White Australian, 6.73 per cent; Bluestem, 6.61 per cent; Little Club, 6.59 per cent; Sonora, 6.39 per cent, the general average being 7.03 per cent. As to the proportion of protein which passed into the flour in each variety the following will show the relation by varieties : White Australian 80.2 Bluestem 79.4 Little Club 84.4 Sonora 85.1 Gluten. — The nature of gluten has already been discussed in the earlier pages of this bulletin and need not be repeated here. The per- centages set forth in the table refer only to the chemically determined gluten consisting of the gliadin plus the glutenin. Considering the relation of gluten to total proteids in wheats and their corresponding flour, the average relation is as follows : Wheats. Flours. White Australian 83.9 96.1 Bluestem 82.6 97.1 Little Club 77.0 98.6 Propo _— 98.8 Sonora 81.7 93.1 The relation of gluten proteids to the total proteids is very different in these flours from that existing in the common wheats of the Middle West. Snyder has stated that the best bread-making qualities of a flour obtain when the gluten proteids are about 85 per cent, of the total proteids. If this is also true of the soft wheats then we may attribute a poor quality of our flour in part at least to the unbalanced relation of gluten to the total proteids. The averages for each type namely, Bluestem, 97 per cent; Club, 97 per cent; Australian, 95 per cent. ; Sonora, 95 per cent. ; show how far different this relation is from that found in eastern wheat. The quantitative, wet-gluten determination was carried through with a considerable number of the flours, but the results, as compared with the chemical determinations, were so inconsistent that they will not be given. The wet gluten as determined was in each case dried and the per cent, of dry gluten determined. These figures are fairly consistent and reliable. Subtracting the percentage of dry gluten from 100 gave the per cent, of moisture held by the gluten. The range of variation was from 53.3 per cent, to 64.3 per cent. ( ?) The relation between the moist- ure content and the expansions made on the gluten are fairly constant on averages. The higher the amount of moisture retained by the wet gluten the larger the expansion. In a general way the expansion 5— b212 378 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. fluctuates with the amount of gluten. There are certain distinctive characteristics of these soft white-wheat glutens which are of interest at this point. The gluten test as quite generally made where flour is studied is not at all satisfactory when applied to soft wheat flours. The first diffi- culty encountered in its application is the small amount of the proteids contained in the flour. In attempting to wash a flour with a low gluten content, the proportion of gluten is so small that it makes it almost impossible to get the fine particles into contact before many are carried away with the water. WASHED GLUTEN TESTS NOT RELIABLE. The nature of the gluten is a second difficulty. It acts entirely dif- ferent in the hand from eastern flours. The first difference is noticed in the dough ; a soft wheat dough can be distinguished very easily, espe- cially if not of the best quality, by its being perfectly smooth on the sur- face after the dough has been worked and is ready for washing. The standard dough is soft and spongy, while the soft wheat dough is firmer and more tenacious, and works very much like a soft putty. The dough on being worked has a marked tendency to stick to the hands and the utensils. The standard dough, while also having that quality, does not have it to the same degree. The two doughs differ much in this respect, that, while they are both tenacious, the standard dough is very cohesive and will not permit its body to separate while the soft wheat dough will in nearly all cases. Of the total fifty-eight doughs made, only three or four approximated the standard in their handling qualities. The next noticeable feature these doughs present is in the surface of the doughs when placed side by side. The poorer dough has the smoother surface. The better the quality of the gluten the more uneven is the surface. There are no abrupt grooves or ridges upon it, but there are small, circular, uneven, bullet-like prominences. The further in the process this dough goes the more pronounced this becomes. They are especially noticeable in kneading the dough back the second or third time. On a poor-gluten flour this structure is never seen, not even in kneading back. The more a dough is worked after raising, the less noticeable these irregularities become. Their appear- ance on the dough, after making the water-absorption test, generally i^ives a very fair idea of what is to be expected in the volume of the loaf. In washing a poor and a good quality of gluten from flour there appears again an indication of the relative qualities of the good gluten dough, the gluten masses appear distinct, even from the very begin- ning, and they are much more apt to stick to the dough ball than to the hands. The standard never sticks to the hands. The particles may occasionally be separated from the mass, but not so often as those from the poorer gluten doughs. On washing a dough of inferior quality the Bulletin 212] CALIFORNIA WHITE WHEATS. 379 gluten masses do not appear as soon ; when they do become visible, they are not distinct and clean, but mixed with more starchy paste. This will stick to the hands and apparently has little affinity for the ball of dough. The very poorest doughs will go to pieces in the process, and always tend to form a paste rather than a separation, and it makes lit- tle, if any, difference even though the wash water be used drop by drop. A good washed gluten will be firm and very much like gristle at first, but will work down after awhile to a very elastic and well-mixed mass. The gluten of poor quality will be soft and indifferent, and soon works into a smooth, soft mass that has little recoiling ability, and when placed upon a cardboard to dry, if it is not dried at once, it is very likely to run all over the cardboard, thus showing its low strength. Considering the mechanical separation of gluten, as applied to the soft or white wheat flour, it is not satisfactory, as stated before. In the most troublesome instances only about one half of the amount was recovered. This leads to the belief that perhaps some of the proteids of these wheats are partly soluble in water and are washed away, thus adding to the mechanical loss. Some flour was set for four hours in cold water, filtered, and the nitrogen in the filtrate determined, with the result that from 12.48 to 17.90 per cent, of the total proteids were found water-soluble. As was previously stated, about 97 per cent, of the total proteids in flour are in the form of gluten. Therefore, some of the gluten amounting to the difference in these two percentages must be soluble in water. The alcohol extraction of the residue showed that from 25 per cent, to 58 per cent, of the gliadin was removed. From samples containing small and large amounts of gluten, the total amount of soluble proteids is larger in the high gluten flours and gradually falls as the gluten content decreases. The decrease in the soluble pro- teids is not as rapid as in the gluten content, so that the percentage amount of soluble proteids to the total amount of proteids gradually increases and is highest on the flour with the lowest total proteids, thus tending to concentrate the error in the method upon the poorer grade of flour. Gliadin. — Gliadin has been given much consideration in most dis- cussions of flour. It seems hardly worthy of so much stress as has been given it, especially as regards the white wheats. The gliadin is said to impart the tenacity and adhesiveness to the gluten. While this may be largely true, it does not seem to apply so generally to the white wheats. The total average of gluten in the form of gliadin is less than 50 per cent. The standard contains 53 per cent., which is lower than is usually found in eastern spring wheat flours. There is a very decided difference in the tenacity of the average Cal- ifornia flour gluten and the standard; the Calif ornian being the more tenacious and very soft, and still has the lower amount of gliadin, not 380 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. only as figured on the gluten, but those that are figured to the total amount of proteids, and contain a lower percentage than the standard on the same basis. An examination of the table shows that in nearly every case the gliadin content of the flour is higher than that of its corresponding wheat, and that this difference is much more marked in the wheats carrying the larger per cent, of protein. While the gliadin increases towards the outside of the kernel, there are some instances in which the reverse appears true, which may be inferred from the lower percentage of gliadin in the flour than in the wheat. In one sample the gliadin-number in the wheat and in the flour remains the same. Since all of these percentages are found, they would sug- gest that variations in every way in the distribution of the gliadin in the grain do occur. The data is, however, insufficient to fully establish this as a fact. Gliadin-N umber. — By the gliadin-number is meant the percentage which the gliadin is of the total protein. In most cases the gliadin-number is increased in milling, that is, the flour shows a larger percentage of gliadin than the corresponding wheat, thus showing the wheat to carry a larger percentage of gliadin in the inner portion of the grain. The average gliadin-number for these sam- ples was 48.6 for the flours as against 33.4 for the wheats, or an average increase of about 4 per cent, by milling. The range in gliadin-numbers was between 34.2 in No. 268 and 69.3 in 41a. Considering the matter by varieties Propo leads with 51.6. Were the gliadin-number the only factor which should be considered in relation to the baking value, or even the determining factor, then Little Club flour with an average of 51.6 should stand close to Propo, but that this is not so is not only the common experience, but is also shown in the fact that the average volume of the Club loaves was only 76 cubic inches as against 83 and 85 cubic inches, respectively, for White Aus- tralian and Bluestem. That the effect of gliadin ratio may often be overshadowed by the total amount of gluten is clearly shown by a series of bakings made from flour having the same gliadin ratio (50:50), but a varying total gluten content. The gluten content of the flour and the volume of each resulting loaf is shown below. The series of loaves is shown in Figure No. 16. No. Gluten. Volume. 8 10.11 97 cu. in. 9 9.37 87 cu. in. 10 6.92 83 cu. in. 11 5.50 66 cu. in. 12 4.70 61 cu. in. Here it may be seen that notwithstanding there is the same gliadin- n !i mlxr the volume of loaf follows the order of the totnl protein. Bulletin 212] CALIFORNIA WHITE WHEATS. 381 382 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. Loaves per barrel. Volume of loaf, cubic inches. . Weight of loaf. Loss in baking, per cent. Absorption- Ash. Non-gluten protein... Gliadin number- Total gluten. Gliadin. Total protein. Moisture. Ash. Non-gluten protein Gliadin number. Total gluten. Gliadin- Total protein- Moisture. t> i> i> 55 35 oo oo «0 t~- HO OS CO CM i-H* M* CO* 00* © CM* O Id 00 CM iH OS OS l> CNI OS t-I CO rH OS t-* CM CM* 00 © in in in •<*<■*»< m m -3i lO t^iocoosccioco^ os ■* in in -*■*-* m in -<* rH CO "* Nffi cp' m co ■* CO CO 00 rH lO S" in OS* CM* 00* ■■# co -# -* CO CM 00 t-" i> co CO CO in in in" t<00 lO 00 ■* CO* rH CO in 00 rH t- © m co -# os co co" co* co" cm cm I ifl CO CO CO CM CM CM SO t-*l>l> t> co in in in co' co' cm* cni -* in os "* »> t> o oo oo CO CO CO CM CO COrHOSinCMI>tM(N in* co' rH co' O i-H H* in COCOCOCMCOCOCOCM ooosoot^t>m^m i> inrH-HH-«t.coinoot--*t>in ■^m-^-*-*cocMco CO ■* CM CM CM CM CM i CO J> CM Hi l> t- < OS rH OS* GO* X CO* CO* CO* 00 85§8§8SSSSS l-J i-i 00* CM CM* CM* CM* ri rH © r • O cm co co ti£ CM M CM CM O" 000CMHoooot--ooooi> 06 ■>* lO CO rH CO 00 rH CM CM OS tH HH I oom^t-t-cooocwt~incpt-< CM-*©©©©©CMCO©©©l>- 0> rH* CO* CO* tJH CM* rH* rH rH* CO* CO* CM* CO CO rH ©050s-*co-*oooooot-rHoo m ©' CM CyJ CM I> rH rH* CO CO* O CM* rH ©' ininmm^mmin-Sh-^imin in t> 00 CO t> HH CM CO CO CO rH (M CO CM t- io-*-*-^inmco-*^*-H*i>co-* -fi rHQOeOGOCOCOCMCOCOCOCO 0'*t^.t-COrHCO'*rHininrHCM g-^COrHCMCOOOSI>rHinop^ coinincoin-^co-^io-^-^co oot^t-r-cocococommininm co CO -# CO CO CM CO CO CO Cv CM CM CM 1 ■*CM-*C0H;lCOCNlCMCMCMCMCMi ooooi>t>t>cococomminmin COCRHHrHCMCMinCMt^COOcMCp ^ CO CO 00 t> O CO rH CC lO 00 rH cR CMCO(MCMCM-*COCOCOCOCOCOCO ■*^coNt»i> OS t> OS 00 © 7-^ t~ CO ^ rH CO CM OS CO rHin©H -* co COeO-*-*CMCMCMCMCMCMrHrHCM CM HH m CM rH CM CMfCMt-rHI>O0CM0O CM t- os co co ■>*< h< r- cm co co CM © C~ J> l> 00 00 b- CO CO CO 00 CO* OS* CM rH rH* -^t* OS CM* OS CM O". CO* CM* r-t £ lO t» 35 CM rH co m © CM 3C © CM CO t- 25 JO 50 CM CM CM Bulletin 212] CALIFORNIA WHITE WHEATS. 383 * 5 '5 M 2 -5 L1 °° So So 83 So t- <© «o jS X* l> OS t~ OS Os t- •* t T). ■* ■* TJ1 •* Os x° O) ■<* o w n a H ©' OJ LO ^ H O N O ■<)( io lo a io lo ifi os . CS I eo © m ** to -* eo iA ■* 25 -* ■* ■* CO in r-t CO CO 5-1 CO CO 1 13 ■* }) n H H 1 8 47.2 58.2 52.4 49.8 54.9 50.1 48.1 CS X X © -^ OS X I> oo n t^ d <*' ■* ■* CO 4.43 3.01 3.26 3.15 2.23 2.35 2.44 B eo" 4.43 4.82 3.83 3.27 2.67 2.47 2.27 OS CO eo' o cs co ■* eo ^ t-i co co co m © cjs fc~ os' oo i> co m° ■* •*' os m CO eo eo* eo' co' 1-4 eo" eo eo' co" r-l i-H rH r-l r-l i-H i-l ■ Q I> CO CO O 00 CO X © OS OS l>r~CS i-H* CO* rH* rH* i-H i-H rH Si 00 CO © CO •■# X CO "# J> 25 CO r-4 Tt< tH CO i-H CO 1-3 r-" r-I rH r-" •<* eo os co -* co m co co' © x I-*' co* <* m" co co co co co co eo -*' eo m © t- c- »o o CO CD I> OS t^ CO CO x x' t> co' id m' m' 3 co X CO ■* co ■* «> OS co co eo ■* rH o cs ■«*< m -* ■* co eo co eo in co' Nt-nOKMH co co -# m co co co eo eo co' c-i co' co' c J 85 CO 3S.83$$2 O O Cs X* t^ co' co' 1-H t— 1 eo 12.12 11.84 11.98 11.77 11.09 12.48 12.90 8 CO* r-i in rH m o t^co t~r- t- CO CO CO CO CO IX X OftON OS t^ in" t^* i> co" o eo co o m CO* CO* rH CO" CO COOSCO^Ht-COCO > co co co m '-i co in "Z CO r- rH CO CO CO "S os os in in in -<* ■>* m >* o os in co CO CO CO CO CO X ■* OS CO oo th" eo" c-i ■<* in m m © © ^ © © co © co co t~ os" t-^ t> co t>" SgiS l> t>© l> mo x m co in -<* co co eo co' co* CO OS -t rH X t~ © OS t~xxxF-xco r- co co co co co co co co ?2?2g£k5S£ rH CO CO X CO OS co in t-' ©' OS x' 00 Os CO* X* Mtin-^-^-^Tti'^i ■* © © co t- © in © x CO* X* ©' i-H t-H X* CO* ©" in © X "* rH © in r^ m in Ss in m m ■* m -<*-*-# tj< © ■* m rH eo ©o •>*i m< in in ^ CO © l> t-- i © © m in eo eo co -^ eo co co t~ in in eo' co co' 888S © © in in co -# eo eo co ■ S© ■* os © i CO 00 rH CO i ©X mi-H OS CO © t~- © t- x © ■* ->* co os os eo in x © t- m © ©" m ■* m ^* eo eo co eo os m x in os co © co' co" eo" eo' r-* co' co' x" t> oc it-* co' t>* t>" co co" eo' co' co co* eo* os •* i <* in ■ 3 7.88 7.65 7.25 7.09 7.32 7.09 8.62 8.21 9.33 9.20 6.96 6.83 6.54 6.42 7.80 7.28 6.74 6.61 7.64 7.38 4.71 4.71 4.94 4.82 5.31 5.18 6.54 6.31 5.02 4.90 5.10 5.10 6.65 6.65 6.00 6.00 1 5.74 5.74 5.56 5 .49 •a s a a 2§ 2 2 2 25 17a 163 19a 480 320 51a __ — 41a 289 Average 253 266 259 249 -__ 317 268 254 228 269 Average 97.0 4.23 55.3 53.7 97.8 3.75 52.9 51.7 96.9 3.83 54.0 52.4 95.2 4.31 52.5 50.0 98.6 4.55 49.5 48.8 98.1 3.15 46.1 45.3 98.2 3.27 50.9 49.8 93.3 5.42 74.5 69.3 98.1 3.58 54.2 53.1 97.0 4.01 54.4 52.7 10.0 2.27 48.1 48.1 97.6 2.47 51.2 50.1 97.6 2.58 49.8 48.5 96.5 2.51 39.8 38.4 97.6 2.67 54.5 53.2 100. 1.75 34.3 34.3 100. 2.47 37.1 37.1 100. 2.47 41.2 41.2 100. 2.87 50.0 50.0 98.8 2.45 45.1 44.5 52.9 52.9 53.5 52.4 50.9 47.9 51.8 53.8 47.6 51.5 50.6 52.1 48.2 53.8 50.3 51.8 54.4 51.1 48.5 51.2 13.0 I 93 14.0 93 10.0 92 11.2 92 13.0 91 6.0 89 12.6 89 12.1 88 11.0 88 11.4 90.5 11.0 61 9.4 63 12.0 69 10.2 69 7.9 71 6.7 76 11.7 77 11.0 77 8.5 81 9.8 71.5 271 274 285 278 271 286 273 276 269 276 275 283 269 284 285 285 281 278 287 281 In Figure 17 (upper row) is shown the volume and character of loaves produced from certain flours of these wheats, No. 5 showing a loaf from a particularly good type of Little Club wheat flour from the crop of 1904, which gave a volume of 86 cubic inches ; No. 7 made from a Sonora flour, also of the crop of 1904, but having a volume of only 76 cubic inches ; No. 6 being from a Little Club flour, crop of 1905, and showing a volume of only 71 cubic inches. In the lower row of the same plate are three illustrations showing that an increase of the gliadin ratio does not entirely govern the volume of loaf. The flours selected to show this had a widely varying gliadin number, but the gluten content was essentially the same, viz. : Number. r-ei, ££ Volume. 268 _ 5.10 5.22 5.02 34.66 48.52 54.65 76 272 82 317 71 388 UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION. Spilfc*'-r ' «# ; . *»%gH be^^^^SSh w- !>f ' -**''^KB BJ15»**'r*^S^^l 'fl If,': *vB ■fry ; ^H ► 1 - '^ I' « 1 ♦ V 1 ' ' ' j 1 « <. ■ • * -'J I^'-* : | H i | • | *' ■ i ' ■ , * 1 ■ 1 % *V.?\ ' u ^B ^1 *i * • '* 1 ^B ■ ' ' ' 1 I' '» ■ '^V* /';-•*•* '"«..' .**■ ^i 1 ^7..:.\..',.;:J ^L_j 2 ^L<0" i ^*$^H P^^wWfv^^^nH KRFi " '--:-^PM P£ >^?3f^H ■'{•.■'!;.■■ ■ • 1 ' • ■■>■■ ■•': ■ *•$;','!. B 's.i ' •/V'.iVfV • " 1 ^^H " ■ V^&V'fc-i >•/•' 1 ^K ■ ' •>.' v >» v • I:' ; - > :,"• ;.;';••' ■ ;:V. .".;-:. ■W I 1 ' ^H ^H KA.; 2g ^. J E. '■•.^..C?g"."l.'..;.;^^ Fig. 17. — Relation of volume to gliadin ratio. First, the higher the gluten the larger the volume of loaf, other things being equal. Second, it seems to further show that an increase in the gliadin ratio is favorable to the production of a better loaf. This, together with the fact that the gliadin number and protein content of these wheats are both relatively low would seem to indicate that the generally poor quality of these flours is due to a lack of development of glutenin rather than of gliadin. Third, the absorptive power in these wheats would seem to have no close relation to the loaf volume, as the loaf volume varies widely in these two groups while the absorptitve power remains essentially the same. Bulletin 212] CALIFORNIA WHITE WHEATS. 389 Table No. XX shows that the volume of the loaf is not parallel with the gliadin number. There is shown, however, a somewhat general relation between the volume of the loaf and the percentage loss in the process of baking. This relation is quite constant. The larger the volume of a loaf, the larger the amount of loss in baking and the lighter and whiter the bread becomes. The whiter and lighter loaves have been shown to be the more nutritious than heavier and darker ones. These two characters are very important then, and since the amount of loss in baking is an indication of each, when the comparison is made between breads from similar flours, it is a valuable determination. The number of loaves of bread of the same size that a flour will yield is a matter of considerable importance and one that is very carefully considered by the bakers. The ordinary housewives would do well to pay some attention to this feature. In the flours studied this variation ranged from 260 up to 289 one- pound loaves per barrel and in the case of standard 297 loaves per bar- rel, with a volume as high as 108 cubic inches. Texture. — The texture of the loaves is seen on cutting them open after they have cooled. In deciding upon this, account is taken of the color of the crust and crumb, the crust should present fine even pores with no roughness or cracks. The crumbs should be uniform through- out as regards evenness and the size of the pores. The body should be moist, soft, and friable. When touched with the finger, it should leave no dent. The membraneous partitions between the pores should be even and thin. In no case should there be any unexpanded masses either glutinous or floury. In general, the texture of loaves from these flours was poor, not that it was due to insufficient working of the dough or insufficient time ir rising, but rather to the quality and quantity of the gluten. In many instances the loaf broke, and in others the crust remained intact but the crumb had not developed evenly. We may say that those flours with less than 5.25 per cent, proteids can not be baked into well-formed loaves under our conditions. Were it attempted to have them raise to the same height in the pan as is common with eastern flours, there would be few that could stand the test. SEASONAL EFFECT ON CHARACTER OF LOAF. The following illustration (Figure 18) fairly represents the general difference in the flours as affected by the season as shown in the bak- ing. Nos. 1 and 3 were from the crop of 1904 and Nos. 2 and 4 from the crop of 1905, all the flours of the latter season giving poorer results than those of 1904. 390 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. The figures for the loaves are subjoined : No. 1 (62a). No. 3 (19a) 1905 No. 2 (231). No. 4 (10a) Total protein _ Gliadin Gliadin number Volume of loaf. 7.97 4.15 52.0 90 cu. in. 8.62 4.31 5.00 8.62 2.33 92 cu. in. 78 cu. in. 7.08 4.43 62.6 81 cu. in. prT^T^KSH mm. -.•*. * $■ HPT : "- v ^B 1"" - * -* .-tIiH V * * v M . . ^m Ti ; ' T .'M 1 < .'".<*■ ■ ^--- ■ ■ ). . . r r •* ■ * f. . • » .>'..<■ '^H \ V^M 1 \ ''■{■ *- H ■ *'> ;.,<;• ■ *V >;;t 1 i y .-■.'. | ^H . *> ^^1 ' • "' . .'* ' ■ ' A ' ' A Y'" ■ I * ■".;. y 1 ^B i !^| ■'.'.,/V/' ;.| • > ^1 1 ;•''.•,-.»" -.' ■ ^^^^^B , -? *,'«'*„ '.". ■■■■■-•'.'■ l ^ B Fig. 18. — Showing difference in loaf as affected by season. Acidity. — The acidity of Californian white wheats is rather low. This may be expected when we remember that the latter part of the growing season is passed in a warm and dry condition, there being no rain to keep the grain green. Then, too, the grain is well matured and perfectly dry by reason of being left standing so long before the harvest can be completed. So there is very little immature or "musty" wheat. The flour contains less fat and less branny portion with foreign particles, thus the chances for fermentation are fewer, and the acidity lower. The determination was made on five grams of flour using one tenth sodium hydrate with phenolphthalein and the result calculated to lactic acid. The range was from .049 to .165 per cent and averaging .095 for all. The following tabulation gives the maximum average, and minimum for the flours from the different wheats. Kinds of Flours. Maximum. Average. Minimum. Bluestem _ _ _ .1086 .1650 .1485 .0976 .0879 .0999 .0890 .0945 0950 .112 .0660 Australian _. _ -_ .088 Club .0495 Sonora _ _ _ _ _ _ _ .088 Average for all__ Standard _ Bulletin 212] CALIFORNIA WHITE WHEATS. 391 For the purpose of comparing the proximate analysis of the type of wheats with the corresponding flours, those samples which were used for milling and baking tests were subjected to complete analysis and the results are contrasted in the following table : Australian. Bluestem. Little Club. Sonora. 3 o e m 9 3 o 9 2 o c 3 2 o c Moisture 10.34 1.73 8.39 2.39 1.42 2.67 13.24 .49 6.73 .19 1.00 3.34 11.88 1.69 8.32 2.78 1.60 2.82 13.31 .47 6.61 .09 .96 3.31 12.03 1.87 8.31 2.69 1.57 2.94 13.13 .45 6.59 .12 .95 3.39 12.29 1.69 7.52 2.12 1.41 2.48 13.77 Ash .46 Total protein 6.39 Crude fiber .07 Nitrogen-free extract — Fat 1.10 Gliadin 2.78 Ash. — The ash of these wheat flours is very low, averaging .55 per cent, and ranging from a minimum of .32 per cent, in Little Club 253 to a maximum of .72 per cent, in Bluestem 260. Fat and Fiber. — Both of these groups are so low as to not appre- ciably affect the flour. The fat averages but .98 per cent, as against 2.24 per cent in Minnesota flours (Minn. Bui. 74, p. 157), and 1.85 for Canadian wheats (Bui. 50, Central Exp. Farm, Ottawa, Canada). This low fat content may explain the high keeping quality of these flours. Certain it is that the Minnesota "Standard" brought from Minnesota at the beginning of these experiments has deteriorated very noticeably within six months, while the native flours do not show any appreciable change. BRAN, SHORTS, AND LOW GRADE FLOURS. Bran, shorts, and the low grade flours are the by-products produced in the manufacture of flour. The floury, white content of the grain is the valuable portion. The by-products consist of the fibrous coverings of the kernels, the germ and unavoidable loss of the starch w T hich is removed along with the undesirable parts. The yield of each depends upon the 'kind and condition of the grain, upon the method of milling and upon the skill of the miller. By improperly supplying the grain to the rolls and manipulating of the streams after bolting, a large amount of flour may find its way into the feed stuffs or some of the feed stuffs may be turned into the flour streams and thus affect not only the color and quality of the flour, but also impair its breadmaking quality and its nutritive value. The bran and shorts are not very different either in the nature of the material or in the composition. In years past, when the flour was not so completely removed, the shorts had con- siderable more value as a foodstuff than bran, as it contained considera- bly more of the middlings which the then used process could not reduce, the bran being left in a coarser condition. But the improved methods 392 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. have swept away this difference. The shorts is now a little more than finely ground bran with perhaps some ground screening and the sweep- ings added to it. The low grade flour is composed largely of the germ parts, the very fine particles of bran and fibrous parts under the bran which are una- voidably obtained in the middlings. To this must be added the very fine specks of dust and hairs of the surface of the grain which were not previously removed, and the small amount of flour that is lost from the chop produced in removing the above debris. The amount thus turned into low grade flour may vary considerably, depending upon the condi- tion of the grain, the process and the kind of flour being produced When milling for a straight grade flour from soft wheat, very little low grade flour need result to make it comparable to eastern straight flours. In commercial milling, the bran and shorts may amount to 22 or 25 per cent of the grain used and the low grade flour from 2 to 10 per cent, or even more. On a small experimental mill it would be impracticable to get large yields of flour, and it is not necessary in order to obtain comparable results. The attached Table No. XXI gives the results of the determinations made on the products. While they are comparable among themselves they are lower in every respect with the exception of the proteids, which are higher than they would have been had they been obtained in commercial milling. TABLE XXI.— SHOWING AVERAGE ANALYSES OF BRAN, SHORTS, AND LOW- GRADE FLOUR FROM WHITE WHEATS. BRAN. Bluestem. Moisture. Ash. Total protein. Fat.* Fiber. Maximum 13.80 12.84 11.36 5.71 5.29 4.73 12.44 10.39 8.62 2.73 2.27 2.06 13.11 Average 11.55 Minimum 9.76 Club. Maximum __ 13.57 12.19 8.86 5.90 5.59 4.97 14.04 10.73 9.01 2.87 2.67 2.52 12.03 Average 10.61 Minimum 9.44 Australian. Maximum .__ 13.53 12.80 11.86 6.01 5.29 4.46 15.22 10.72 7.80 2.53 2.42 2.29 10.96 Average __ _ _ 10.17 Minimum __ _ _ _ _ 9.47 Sonora. Maximum _ 12.85 12.60 12.33 5.20 4.82 4.29 10.11 9.04 7.97 Average __ 2.35 8.41 Minimum •Determination made on < nmposite sample. Bulletin 212] CALIFORNIA WHITE WHEATS. 393 SHORTS. Bluestem. Maximum Average . Minimum 14.12 13.22 12.30 4.71 4.10 3.10 14.91 11.79 10.03 4.26 3.99 3.48 7.57 6.98 6.00 Club. Maximum Average . Minimum 13.99 12.24 11.29 4.84 4.25 2.89 14.28 12.09 9.83 4.51 4.27 4.06 8.17 749 6.44 Australian. Maximum 14.02 12.43 11.51 4.89 4.31 3.68 16.74 11.93 8.70 4.35 4.08 3.71 7.77 Average 7.05 Minimum 6.49 Sonora. Maximum Average . Minimum 12.85 12.60 12.33 5.20 4.82 4.29 10.11 9.04 7.97 3.81 5.79 LOW-GRADE FLOUR. Bluestem. Moisture. Ash. Total protein. Fat.* Tiber. Maximum _ 14.14 13.30 11.68 2.47 1.82 1.25 13.32 9.63 7.80 2.92 2.67 2.27 1.86 Average 1.39 Minimum 1.07 Club. Maximum 13.91 13.01 12.30 2.85 1.35 1.32 11.80 9.18 7.08 3.39 2.82 2.36 2.03 Average 1.72 Minimum 1.37 Australian. Maximum 13.71 12.88 11.58 2.73 1.96 1.42 13.56 10.05 7.97 3.15 2.70 1.82 2.64 Average 1.98 Minimum 1.50 Sonora Maximum 13.70 13.61 13.52 2.14 1.86 1.63 9.49 8.61 7.72 Average 3.03 1.67 Minimum * Determination made on composite sample. 6— b212 394 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. Under shorts, there is a maximum of total protein in the Australian wheats given of 16.74 per cent. This is of interest in that it suggests a wheat with a high protein content. Tracing it back to the wheat we find it has 15.22 per cent in the bran, 13.56 per cent in the low grade flour, 11.72 per cent in the whole wheat and only 7.80 per cent in the flour. This, then, is a case of high protein wheat yielding a flour with a rela- tively low amount. This suggests the need of looking further than to the nitrogen content of a wheat as indicative of its value for the improving the bread-making quality of the same. This same wheat has also a fair amount of gluten, having 90 per cent, of the total proteids in the form of gluten. SOME CONCLUSIONS. (1) The California white wheats have a low nitrogen and protein content. (2) The larger normal kernels usually carry a higher per cent, of nitrogen than smaller normal kernels of the same type. (3) The California white wheats are relatively high in fiber and low in ash and ether extract as compared with the hard winter wheats. (4) The wheat crop of 1905 contained a uniformly lower nitrogen content than did the crop of 1904. (5) The overlap of gluten nitrogen in the salt soluble extract is rep- resented in the case of white wheat meals by the factor .15 per cent. ; for flour .22 per cent. (6) The polariscopic method for the determination of gliadin has proven very reliable. (7) The mechanical separation of gluten in the case of this class of wheats is very unsatisfactory. (8) The California white wheats contain a larger proportion of their total protein in the form of gluten than do most other wheats. (9) The gliadin-number of these wheats is much lower than for those of the middle west. (10) These wheats ordinarily produce a very white flour which bakes darker than the tinted flours from winter wheats. (11) The water absorption of these wheats is relatively low. The white wheat flours absorb about 52 per cent., while the hard spring wheat flours absorb about 58 per cent. (12) Loaves showing the greater loss in baking, other things being equal, are the lighter and whiter. (13) Glutens from white wheat flours are not tenacious according as they contain more gliadin. (14) The gluten of these wheats hydrolyze more than for other types of wheat. (15) The glutens of these wheats are usually inferior in quality and dull in color. STATION PUBLICATIONS AVAILABLE FOR DISTRIBUTION. REPORTS. 1896. Report of the Viticultural Work during the seasons 1887-93, with data regard- ing the. Vintages of 1894-95. 1897. Resistant Vines, their Selection, Adaptation, and Grafting. Appendix to Viti- cultural Report for 1896. 1902. Report of the Agricultural Experiment Station for 1898-1901. 1903. Report of the Agricultural Experiment Station for 1901-03. 1904. Twenty-second Report of the Agricultural Experiment Station for 1903-04. BULLETINS. Reprint. Endurance of Drought in Soils of No. 186. the Arid Regions. 187. No. 128. Nature, Value, and Utilization of Alkali Lands, and Tolerance of 188. Alkali. (Revised and Reprint, 1905.) 189. 133. Tolerance of Alkali by Various Cultures. 190. 147. Culture Work of the Sub-stations. 191. 149. California Sugar Industry. 192. 151. Arsenical Insecticides. 153. Spraying with Distillates. 193. 159. Contribution to the Study of Fer- mentation. 162. Commercial Fertilizers. (Dec. 1, 194. 1904.) 165. Asparagus and Asparagus Rust 195. in California. 197. 167. Manufacture of Dry Wines in Hot Countries. 168. Observations on Some Vine Dis- eases in Sonoma County. 198. 169. Tolerance of the Sugar Beet for 199. Alkali. 200. 170. Studies in Grasshopper Control. 171. Commercial Fertilizers. (June 30, 201. 1905.) 172. Further Experience in Asparagus 202. Rust Control. 174. A New Wine-cooling Machine. 203. 176. Sugar Beets in the San Joaquin Valley. 204. 177. A New Method of Making Dry Red Wine. 205. 178. Mosquito Control. 179. Commercial Fertilizers. (June, 206. 1906.) 180. Resistant Vineyards. 207. 181. The Selection of Seed-Wheat. 208. 182. Analysis of Paris Green and Lead 209. Arsenic. Proposed Insecticide 210, Law. .183. The California Tussock-moth. 211. 184. Report of the Plant Pathologist to July 1, 1906. 185. Report of Progress in Cereal In- vestigations. The Oidium of the Vine. Commercial Fertilizers. (January, 1907.) Lining of Ditches and Reservoirs to Prevent Seepage and Losses. Commercial Fertilizers. (June, 1907.) The Brown Rot of the Lemon. California Peach Blight. Insects Injurious to the Vine in California. The Best Wine Grapes for Cali- fornia ; Pruning Young Vines ; Pruning the Sultanina. Commercial Fertilizers. (Dec, 1907.) The California Grape Root-worm. Grape Culture in California; Im- proved Methods of Winemak- ing; Yeast from California Grapes. The Grape Leaf-Hopper. Bovine Tuberculosis. Gum Diseases of Citrus Trees in California. Commercial Fertilizers. (June, 1908.) Commercial Fertilizers. (Decem- ber, 1908.) Report of the Plant Pathologist to July 1, 1909. The Dairy Cow's Record and the Stable. Commercial Fertilizers. (Decem- ber, 1909.) Commercial Fertilizers. (June, 1910.) The Control of the Argentine Ant. The Late Blight of Celery. The Cream Supply. Imperial Valley Settlers' Crop Manual. How to Increase the Yield of Wheat in California. CIRCULARS. No. 1. 5. .7. 9. 10. 11. 12. 15. 17. 19. 29. 39. 4 6. Texas Fever. Contagious Abortion in Cows. Remedies for Insects. Asparagus Rust. Reading Course in Economic Ento- mology. ( Revision. ) Fumigation Practice. Silk Culture. Recent Problems in Agriculture. What a University Farm is For. Why Agriculture Should be Taught in the Public Schools. Disinfection of Stables. Preliminary Announcement Con- cerning Instruction in Practical Agriculture upon the University Farm, Davisville, Cal. White Fly in California. White Fly Eradication. Packing Prunes in Cans. Cane Sugar vs. Beet Sugar. Analyses of Fertilizers for Con- sumers. Instruction in Practical Agriculture at the University Farm. Suggestions for Garden Work in California Schools. No. 47. 48. 49. 50. 51. 52. 54. 55. 57. 59. 60. 61. 62. Agriculture in the High Schools. Butter Scoring Contest, 1909. Insecticides. Fumigation Scheduling. University Farm School. Information for Students Concern- ing the College of Agriculture. Announcement of Farmers' Short Courses for 1910. Some Creamery Problems and Tests. Farmers' Institutes and University Extension in Agriculture. Announcement of Farmers' Short Courses in Animal Industry and Veterinary Science. Experiments with Plants and Soils in Laboratory, Garden, and Field. Tree Growing in the Public Schools. Butter Scoring Contest. University Farm School. The School Garden in the Course of Study.