I f\cj (y J i.^j. 6 I- GOVERNf/SEMT PUBLICATIONS RECEIVED DEC 2 81983 UNIVERSITY LIBRARY UMlYERSiTY C? CO.^JNECTICUT ISSN 0097-0905 s Quality of Butter and Blends of Butter with Oleomargarine By Lester Hankin and J. Gordon Hanna A cooperative study by The Connecticut Agricultural Experiment Station and The Connecticut Department of Consumer Protection The origin of butter-making is unknown, but presumably it was in prehistoric stages of animal husbandry. Since then man has commonly used butter as a spread and as a fat for cooking. Butter is made from cream, the fatty portion of milk. In the United States only cream from cow's milk is used for commercial butter production but the cream from milk of other animals can also be made into butter When the cream is churned, the fat droplets coalesce and form progressively larger clusters of fat globules. These globules eventually break away from the liquid portion and form the semi-solid or plastic material we call butter The butter may then be washed, colored, salted and then packaged in a variety of shapes and sizes, even in individual servings called pats. Regulations state that butter must contain at least 80% fat. Whipped butter has air incorporated into the butter to make it spread more easily. Although the per capita consumption of butter in the United States has declined over the past 40 years, many consumers continue to prefer butter over margarine for cooking or as a spread because of its distinctive flavor, aroma and cooking attributes. Although commercially produced butter is made from pasteurized cream, microorganisms such as bacteria or yeasts and molds can be introduced into the product from processing or packaging. The flavor of good butter is very delicate and even small amounts of microbial growth can damage its pleasant flavor and aroma. If butter is kept refrigerated below 40° F, organisms in the butter multiply slowly. On the other hand, should the butter be stored above 50° E, contaminating organisms can multiply quickly and deteriorate the product. In this study we examined both butter and blends of butter with oleomargarine for microorganisms as well as for nutrients. Methods Thirty-five samples of butter or blends of butter with oleomargarine were collected at retail stores by inspectors of the Connecticut Department of Consumer Protection. Twenty-three samples were regular butter (one pound blocks or quarter pound sticks), nine were whipped butter, and three were blends of butter with oleomargarine. The Standard Plate Count and tests for coliform bacteria and enterococci were according to Standard Methods for the Examination of Dairy Products (5), chemical analyses by AOAC methods (3), and sodium by atomic absorption spectrophotometry (2). Lipolytic and proteolytic organisms were detected as previously described (1). Results and Discussion The results of microbiological and chemical analyses of the 35 samples of butter and blends of butter with oleo- margarine are shown in Table 1. Microbial. A standard test for bacterial contaminants in dairy products is the test for coliform bacteria. All samples contained less than 2 coliform bacteria per gram which usually indicates good manufacturing practices. It has been suggested, however, that coliform bacteria may die easily in stored butter and that a test for enterococci may be more valid in assessing sanitary quality (4). Only samples 23 and 34 contained enterococci, 220 and 22 per gram, respectively. A standard of not more than 10 per gram has been suggested (4, 5). BULLETIN 813 • THE CONNECTICUT AGRICULTURAL EXPERIMENT STATION NEW HAVEN • JULY 1983 - J . 1 1: I-- Table 1. Microbial and Nutrient Analysis of Butter and Blends of Butter witti Oleomargarine. Sample Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 Brand and Type A & P butter, lightly salted Breakstone's butter, lightly salted Breakstone's butter, sweet Breakstone's whipped butter, lightly salted Breakstone's whipped butter, sweet Cabot Vermont butter Finast butter Grand Union Creamery butter lightly salted Grocers Pride butter Grassland superwhipped butter, lightly salted Hood butter lightly salted Hotel Bar Blend margarine — 40% butter Hotel Bar butter Land O'Lakes butter, lightly salted Land O'Lakes butter sweet Land O'Lakes whipped butter, lightly salted Land O'Lakes whipped butter, sweet Land O'Lakes Country Morning Blend margarine, lightly salted — 40% butter Land O'Lakes Country Morning Blend margarine, sweet — 40% butter Real Gold butter, lightly salted Pathmark butter lightly salted Shop Rite butter, lightly salted Shop Rite butter, sweet Shop Rite whipped butter, lightly salted Shop Rite whipped butter, sweet Shurfine butter lightly salted Stop and Shop butter lightly salted State Brand butter, lightly salted Summer Maid butter Sun Glory butter Sweet Life butter lightly salted Waldbaum's butter lightly salted Waldbaum's butter, sweet Waldbaum's whipped butter lightly salted Waldbaum's whipped butter, sweet 140 70 40 89.000 61,000 >3,000,000 64 25 550,000 500 4,400 3,400 <10 4,400 1,400,000 30 120 15 <10 70 Standard Psychrotrophic Proteolytic Lipoh ji Plate Count== Bacteria Bacteria Bact( j; CFU/g= CFU/g CFU/g CFU 8,700 <10 1,600 40 <10 20 1,500 <10 30 60 <10 30 90 <10 10 l.iffl 52,000 190 51,000 200,000 180 1,000 1,1 [ 620,000 <10 60.000 >300.i 'i 890 <10 340 80 <10 30 320 36 130 14 <10 <10 45,000 <10 4,000 2: 130 <10 45 40 60 10 260 <10 110 970 760 10 <10 20 <10 20 68 7,000 13, 72,000 <10 [, >300,000 >3,000,000 >300,n <10 50 . <10 10 ( 160 150,000 98, '( 750 <10 <10 2,100 12,000 2,700 30 <10 3,400 40 1,'« <10 <10 >300,l( <10 20 ,; <10 25 1 <10 10 a) Slandard Plate Count i.s number of aerobic bacteria reported as number of colony forming units (CFU) per gram. Yeast and mold count is h| cok)n\ forming units per gram. I ' b) A pat or individual serving of regular butter is 5 grams, for whipped butter it is 3.8 grams. c) g = grams; mg = milligrams. The number of bacteria per gram (Standard Plate Count) also provides some information about manufacturing tech- niques. There are no standards for total numbers of bacteria in butter, but in Connecticut, for example, 100,000 per gram (Standard Plate Count) is allowed in ice cream. Only 5 samples of butter had more than this number (Table I ). Because butter is stored at a low temperature, a measure of the number of psychrotrophic bacteria is important. Psychrotrophic bacteria are those able to grow, albeit slowly, at low temperatures and cause deterioration of the butter Although only sample 23 contained a considerable number of psvchrotrophs (>3 million), sample 22 was also high (over 50,000) (Table I ). The two other microbial tests for detecting contaminating organisms were for lipolytic bacteria, those that degrade fat, and proteolytic bacteria, those that attack proteins. Essen- tially only samples 8, 23, 26, and 32 contained a high number of lipolytic bacteria and only samples 6, 8, 23, and 26 contained a high number of proteolytic bacteria. Only samples 23, 29, and 32 contained an appreciable number of yeasts and molds. We do not attach significance to health to the number of microorganisms found in these butter samples. The tests we conducted are useful in detecting organisms that help evaluate manufacturing and packaging techniques and the findings help to assess potential keeping quality of the product. Nutrients. The average fat content in all samples was 81.1%. The nine whipped butters averaged 80.0% and the three blends 80.9%. Only sample number 30, with 78.3% fat was below standard (Table 1). Although less than 80% fat is shown for five other samples in Table 1 (79.5 to 79.9%), the values conform to the 80% minimum when rounded to the nearest whole number The three blends of butter with oleomargarine, samples 12, 18, and 19, claimed 40% butter and 41.0, 41.7, and 41.3% butterfat was found respectively. None of the butter was adulterated with vegetable oil. Butter contains small amounts of protein (designated as Yeasts and Molds Fat, Casein, Sodium, Cholesterol Calories Sample CFU/g^ % % mg/100g'= mg/IOOg No./pat'' Number <2 81.4 1.29 488 209 36 1 <2 81.0 1.73 641 224 36 2 <2 79.8 1.08 5.5 199 35 3 <2 81.4 1.90 635 199 27 4 <2 81.1 0.78 4.8 193 27 5 200 82.6 1.42 516 188 37 6 74 80.8 1.61 607 202 36 7 10 81.6 1.59 750 197 36 8 <2 80.3 1.75 655 201 36 9 120 80.9 2.21 408 190 27 10 6 81.0 1.63 620 203 36 11 <2 80,3 1.23 427 81 36 12 10 79.5 1.36 382 151 35 13 <2 85.9 1.03 604 196 38 14 <2 80.2 1.58 7.5 192 36 15 <2 80.6 1.12 550 207 27 16 <2 80.1 1.28 5.1 217 27 17 <2 79.8 0.81 611 81 35 18 <2 79.9 1.09 14.3 82 35 19 <2 80.5 1.22 589 177 36 20 <2 80.6 1.55 391 147 36 21 580 84.1 0.41 511 185 37 22 >3,000 80.0 1.25 5.5 203 35 23 <2 80.6 1.22 596 191 27 24 <2 81.6 1.23 13.7 192 27 25 48 82.8 1.72 600 213 37 26 <2 81.6 1.36 682 176 36 27 <2 81.2 1.20 627 213 36 28 21,000 80.0 0.86 660 197 35 29 <2 78.3 1.15 469 149 35 30 20 80.8 1.33 445 212 36 31 1,700 83.1 1.60 667 247 37 32 <2 82.6 1.33 14.6 197 37 33 15 79.7 1.31 772 184 27 34 <2 81.8 1.23 12.8 186 28 35 % casein in Table I). The average protein content of the 32 butter samples was 1.35% but the range was wide. The amount of casein left in the butter after churning the cream depends on how much the butter is worked and washed. The three blends averaged 1.04% protein. Fat provides about 9 calories per gram, about twice that supplied by protein or carbohydrate. We show in Table 1 the calories provided by a pat of butter, an individual serving. A pat of regular butter weighs 5 grams and a pat of whipped butter weighs only 3.8 grams since it contains some air. The number of calories per gram of regular and whipped was the same, but the whipped butter contained less per pat (36. 1 per pat of regular butter versus 27. 1 per pat of whipped) because each pat weighed less. The blends contained about the same calories as regular butter Some people are concerned about cholesterol in butter. The milligrams (mg) cholesterol per 100 grams of butter is shown in Table I . The average in the 32 butter samples was 195 mg and in the three blends was 81 mg, since the blends contain only 41% butter Oneserving(apat) of regular butter contains about 10 mg cholesterol. For comparison, one egg contains about 270 mg cholesterol. Sodium interests those who wish to restrict their salt intake. The sodium in the nine sweet butters and blends averaged 9.3 mg per 100 grams (Table I). Those labelled as lightly salted or unlabelled as to salt contained 572 mg. There was little difference in average sodium content between those labelled lightly salted (18 samples averaged 586 mg per 100 grams) and those unlabelled as to salt (8 samples averaged 541 mg). A pat of butter contains 20 to 30 mg of sodium which is about the same as in a saltine. Conclusions Thirty-two regular and whipped butters and three blends of butter with oleomargarine were tested for microorganisms and nutrients. Although there are no microbial standards for butter, only five samples of the 35 examined were considered to contain an excessive number of contaminating microorganisms. Two samples contained many psychro- trophic bacteria which can grow at temperatures in a refrigerator. All samples contained less than two coliform bacteria per gram. All samples, except one, contained at least the 80% fat that is required by regulation. Blends of butter with oleomargarine claiming 40% butter actually contained about 41%. Protein content averaged 1.35% for butter and 1.04% for the blends. The butter averaged 195 mg cholesterol per 100 grams and the blends with 41%- butter 81 mg. The number of calories in a single serving of butter ranged from 27 to 36. The sodium content of the sweet butters and blends averaged 9.3 mg per 100 grams and those labelled as lightly salted or unlabelled as to salt averaged 586 mg. References Anagnoslakis, S. L. and L. Hankin. 1975. Use of selective media to detect en7yme production by microorganisms in food products. J. Milk Food Technol. 3S: 570-572. Analytical Methodsfor Atomic Absorption Spectrophotometry, Perkin- Elmer, Norwalk, CT. Official Methods of Analysis. 1980. 13thed.,W. Horwitz, ed. Association of Official Analytical Chemists. Washington. DC. Saraswat. D. S., G. W. Reinbold. and W. S. Clark. Jr 1965. The relationship between enterococcus, coliform and yeast and mold counts in butter J. Milk Food Technology 28: 245-249. Standard Methods for the E.xamination of Dairy Products. 1978. 14th ed., E. H. Marth. ed. American Public Health Association, Washington, DC. Acknowledgments We thank Michelle Birks. Mar\ Alice lllig. Lucia McLean. Alphonse Wickroski. and Richard Hastings for skillful technical assistance and Frank Zullo and Donald Pignataro for collecting the samples. University of Connecticut Libraries 39153028879239 i,;';:?./.'!;'"i' ■■■■; '''■^'S/'\--K':^}^ *- '.-■' . : N - . 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