Effect of Casein/Fat Ratio on Milk Fat Recovery in Cheddar Cheese

Cheddar cheese was made by the traditional 4.5-h method from three experimental lots of milk, each standardized to casein/fat ratios of approximately 0.64, 0.67 and 0.70. The effect of casein/fat ratio on milk fat recovery was determined. The effects of milk composition on curd firmness at cutting, cheese composition and resulting yield of cheese were evaluated. Correlations between milk constituents and various cheese components were obtained. Milk fat recovery was unaffected by casein/fat ratios within the limits of 0.64 and 0.71. Average milk fat recovery was 91.58 ± 1.73%. Cheese yield was a function of milk protein, milk fat and cheese moisture; and a modified Van Slyke equation predicted cheese yield better than the original equation within the limits of casein/fat ratio studied. Strong negative correlations were observed between casein/fat ratio and cheese fat and cheese fat in the dry matter whereas positive correlations were observed between casein/fat ratio and cheese protein. At constant protein levels curd firmness increased directly with the amount of fat in cheese milk

Enzymes indigenous to milk | other enzymes

Several enzymes have been identified or purified from mammalian milk in trace amounts. Some of these enzymes have specific and established functions in the mammary gland, in milk, or in the newborn (e.g., catalase, lysozyme, lactate dehydrogenase). Their activities in milk may reflect physiological changes or a pathological state of the mammary gland during lactation. They may play a role in gastrointestinal function, nutrient digestion, and delivery to the newborn (e.g., amylases, γ-glutamyltranspeptidase). Others function by protecting the newborn against oxidative damage and bacterial and viral infections (e.g., lysozyme). Some of the enzymes have been exploited technologically (e.g., catalase and lysozyme) and may play a role in dairy foods. This review focuses on individual enzymes indigenous to milk that are not discussed in detail in other sections of this encyclopedia. Their functions, properties, and established functions in milk are described