Protein milk

Milk and egg products are highly desired in pet foods since they supply the highest quaHty amino acid profiles with nearly 100% digestibiHty. Most milk protein concentrates are used for human foods, but some are available to pets (see Milk and milk products). An enormous quantity of whole eggs (qv) derived from egg graders, egg breakers, and hatchery operations are handled as dehydrated, Hquid, or frozen ingredients. 

The mmen is not functional at birth and milk is shunted to the abomasum. One to two weeks after birth, the neonate consumes soHd food if offered. A calf or lamb that is nursing tends to nibble the mother s feed. An alternative method of raising the neonate is to remove it from its mother at a very young age, <1 week. A common example of an early weaning situation is the dairy calf that is removed from the cow soon after birth so that the cow s milk supply might be devoted entirely to production. In this instance, the neonate requires complete dietary supplementation with milk replacer. Sources of milk replacer protein have traditionally included milk protein but may also include soybean proteins, fish protein concentrates, field bean proteins, pea protein concentrates, and yeast protein (4). Information on the digestibiUty of some of these protein sources is available (4). 

Tradblazer whey/milk protein Gum-based mimetics Kraft General Foods... 

Products prepared from soy protein products and resembling chicken, ham, frankfurters, and bacon are available commercially. Soy protein isolates are used in place of milk proteins or sodium caseinate in products such as coffee creamers, whipped toppings, yogurt, and infant formulas (see Dairy substitutes). Soy protein products also are used in snacks and in baked foods. 

Casein. Milk contains proteins and essential amino acids lacking in many other foods. Casein is the principal protein in the skimmed milk (nonfat) portion of milk (3—4% of the weight). After it is removed from the Hquid portion of milk, whey remains. Whey can be denatured by heat treatment of 85°C for 15 minutes. Various protein fractions are identified as a-, P-, and y-casein, and 5-lactoglobulin and blood—semm albumin, each having specific characteristics for various uses. Table 21 gives the concentration and composition of milk proteins. 

A useful property of the red seaweed extracts is their abiUty to form gels with water and milk. Kappa-carrageenan reacts with milk protein micelles, particularly kappa-casein micelles. The thickening effect of kappa-carrageenan in milk is 5—10 times greater than it is in water at a concentration of 0.025% in milk, a weak thixotropic gel is formed. 

Total piotein = milk protein + cocoa protein. 

Cocoa protein = (total nitrogen — milk nitrogen) X 4.7. Milk protein = milk nitrogen x 6.38 appears in parentheses. Total carbohydrate by difference using cocoa nitrogen x 5.63. 

Material is the reaction product of a fatty acid amide of N,iV-dimethylpropylenediamine and epichlorohydrin and hydrolyzed milk protein. 

Phosphates, which react with calcium to reduce the calcium ion activity, assist in stabilizing calcium-sensitive proteins, eg caseinate and soy proteinate, during processing. Phosphates also react with milk proteins. The extent of the reaction depends upon chain length. Casein precipitates upon addition of pyrophosphates, whereas whey proteins do not. Longer-chain polyphosphates cause the precipitation of both casein and whey proteins. These reactions are complex and not fully understood. Functions of phosphates in different types of dairy substitutes are summarized in Table 9 (see also Food additives). 

Ice-cream is a product which has been developed since mechanical refrigeration became available. Ice-cream mixes comprise fats (not always dairy), milk protein, sugar and additives such as emulsifiers, stabilizers, colourings, together with extra items such as fruit, nuts, pieces of chocolate, etc., according to the particular type and flavour. The presence of this mixture of constituents means that the freezing... 

To test for possible toxic effects, rats, mice, dogs, chickens pigs, and fish were fed Pruteen at various levels in their diet, ranging from 30% to 60%. Control animals were fed casein (milk protein) instead of Pruteen. Feeding periods ranged from 28 days to 3 years. The parameters measured are outlined below. 

Polysorbate 80 is an emulsifying agent that is often used in ice cream to prevent milk proteins from completely coating the fat droplets. This allows them to join together in chains and nets, to hold air in the mixture, and to provide a firmer texture that holds its shape as the ice cream melts. 

The structure of whipped cream is quite complex. A coating of milk protein surrounds small globules of milk fat containing both solid and liquid fats. These globules stack into chains and nets around air bubbles. The air bubbles are also formed from the milk proteins, which create a thin membrane around the air pockets. The three-dimensional network of joined fat globules and protein films stabilizes the foam, keeping the whipped cream stiff. 

Carrageenan is a gelling agent that forms a complex with the milk proteins, adding bulk and strength. A small amount will make a large difference in the ability to hold air in the foam. 

Carrageenan is widely used in dairy products because it forms complexes with calcium and milk proteins. It thickens and helps suspend cocoa particles in chocolate milk. It stabilizes ice cream to protect it from thawing and refreezing, and enables it to hold more air. 

GARDNER c D, NEWELL K A, CHERiN R and HASKELL w L (2001) The effect of soy protein with or without isoflavones relative to milk protein on plasma lipids in hypercholesterolemic postmenopausal women. dm J Clin Nutr. 73 (4) 728-35. 

Figure 4, Effect of sample concentration on the distribution of milk proteins on Spherogel TSKSW 2000 column. Instant, nonfat, dry milk was dissolved in mobile phase at the indicated concentrations and 10-fjJL aliquots injected under the conditions outlined in Figure 1.

Figure 5. Redistribution of higher molecular weight milk proteins on the SW 2000 column. Whole milk (100 yL) was fractionated under the conditions iruiicated in figure 4. A 100-yL aliquot of eluant collected from the shaded portion of the profile on the left was rechromatographed as shown on the right.

Dalgleish, D. G., "Recent Advances in the Physical Chemistry of Milk Proteins", International Dairy Congress, Paris,... 

Douglas, F. W., Jr., Greenberg, R., Farrell, H. M., Jr., and Edmondson, L. F. (1981). Effects of ultra-high-temperature pasteurization on milk proteins. /. Agric. Food Chem. 29, 11-15. 

Dairy proteins are rich in nutrients and occupy a unique place of importance in food and human nutrition because of their wide acceptance in the world. Milk proteins are important in the diet because of the many health benefits associated with their consumption. The proteins have long been recognized as natural sources of health enhancing bioactive peptides because of their stmctural and physicochemical components as recently reviewed by Livney (2010). 

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