Buttermilk composition

Milk. Imitation milks fall into three broad categories filled products based on skim milk, buttermilk, whey, or combinations of these synthetic milks based on soybean products and toned milk based on the combination of soy or groundnut (peanut) protein with animal milk. Few caseinate-based products have been marketed (1,22,23). Milk is the one area where nutrition is of primary concern, especially in the diets of the young. Substitute milks are being made for human and animal markets. In the latter area, the emphasis is for products to serve as milk replacers for calves. The composition of milk and filled-milk products based on skim milk can be found in Table 10. Table 15 gives the composition of a whey /huttermilk-solids-hased calf-milk replacer, which contains carboxymethyl cellulose (CMC) for proper viscosity of the product. 

Cultured buttermilk is manufactured by fermenting whole milk, reconstituted nonfat dry milk, partly skimmed milk, or skim milk with lactic acid bacteria. Most commercial cultured buttermilk is made from skim milk. Mixed strains of lactic streptococci are used to produce lactic acid and leuconostocs for development of the characteristic diacetyl flavor and aroma. Buttermilk is similar to skim milk in composition, except that it contains about 0.9% total acid expressed as lactic acid. The percentage of lactose normally found in skim milk is reduced in proportion to the percentage of lactic acid in the buttermilk. According to White (1978), the fat content of buttermilk usually varies from 1 to 1.8%, sometimes in the form of small flakes or granules to simulate churned buttermilk, the by-product of butter churning. Usually 0.1% salt is added. 

The fat obtained by different methods of processing varies in composition and therefore in properties (Table 4.12 Mulder and Walstra 1974). For example, the amount of phospholipid per 100 g of fat is much greater in buttermilk from 40% cream than in whole milk (21.6 vs. 0.9 g), and these phospholipids contain much more unsaturated fatty acids than the whole milk lipids. 

Cultured milk products are manufactured by fermentation of milk or cream by lactic culture microorganisms that produce desirable flavor and rheological properties which are influenced by the composition of the milk or cream, and by the processing conditions used (Richter 1977 Foster et al. 1957 Marth 1974). Cultured buttermilk may be made from skim milk but is sometimes made from milk containing 1.0 to 3.5% milk fat. Some cultured milk products often contain added MSNF and plant gum or modified starch stabilizers to increase viscosity and control whey syneresis. Dextran-producing culture microorganisms are sometimes used to provide needed viscosity to the cultured milk product without the need to add MSNF or stabilizers. Up to 0.1% citric acid or sodium citrate is commonly added as a substrate for... 

Increased recognition of the nutritional significance of components of the MFGM has led to a number of studies dedicated to the extraction and production of MFGM from buttermilk. Specific processes have been designed to obtain MFGM isolates free from other milk constituents, with the explicit objective of their use as bioactive and functional food ingredients. The differences in composition between isolates produced from different... 

Table 13.1. Recommended (ADPI, 2002) and actual Mean Composition of Skim Milk, Buttermilk and Whole Milk Powders (USDA, 1999)...

Kristensen, D., Hedegaard, R.V., Nielsen, J.H., Skibsted, L.H. 2004. Oxidative stability of buttermilk as influenced by the fatty acid composition of cow s milk manipulated by diet. J. Dairy Res. 71, 46-50. 

Buttermilk is a by-product of butter manufacture, in which pasteurized cream is cultured and then churned to produce butter and buttermilk. It has approximately the same composition as skimmed milk, and can also be concentrated and spray dried. Buttermilk provides a distinctive, fresh flavour. 

For fat calibrations of skim milk powder it was impossible to get samples with enough variation in fat content. Owing to the standardization of this product the calibration set is not ideal. All calculated correlation coefficients are above 0.98 with an SEC of 0.09 to 0.31 % (Table 20.8). The latter 0.31 % is found for a combined calibration of skim milk powder and buttermilk powder. The standard error is about twice as high than the separate calibrations, which is caused by an increased variation in the sample composition. On the other hand, samples of milk powder with nonmilk fat give a wide variation of fat content. The SEC value is 0.30. By making two calibrations the SEC value decreases to 0.14 on average. The values of SEP and R obtained for the prediction sets are comparable with those of the calibration sets. 

SECs of0.38,0.35, and 0.34% were calculated for the determination of lactose in skim milk powder, buttermilk powder, and milk powder with nonmilk fat (Table 20.9). These are acceptable in relation to the standard deviation of the reference method of about 0.25%. The SEC for the combined calibration of skim and buttermilk powder and for denatured milk powder are too high for accurate analysis. Similar results were observed for the test set. This is caused by the variation in physical and chemical composition of the samples and by the few specific NIR bands of lactose in relation to the overall NIR spectrum. Therefore many filters are needed for the calibration. About ten filters gave significant... 

For the determination of lactate in buttermilk and denaturated milk powder, the use of a lot of filters (12 in total) gives significant information. The need for so many filters is caused by the variation in physical and chemical composition of the samples and by the few specific NIR bands of lactate in relation to the overall NIR spectrum. 

Ice creams are made from milk fat (usually in the form of (ream), milk solids (concentrated skim milk, milk, buttermilk solids, condensed whey, orNFDM), sweetener (usually sucrose, com syrup solids, or high fructose com symp (HFCS)), 0.2-0.5% stabilizers, and flavoring. These ingredients are formulated to meet the desired Standard of Identity (Table 14.10). These Standards of Identity dictate compositional limits as well as some aspects of flavoring. 

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