Milk-Clotting Enzymes. 2. Estimating Cheese Yield Losses from Proteolysis During Cheese Making

¹ Food Research Centre, Research Branch, Agriculture Canada, Ottawa, Ontario K1A OC6 Canada

Some milk-clotting enzymes are more proteolytic than calf rennet during cheese making. Reductions in cheese yield can be estimated by comparing levels of N (as protein) in wheys produced by calf rennet and those enzymes. A higher level of N in whey means that more casein is hydrolyzed than with the control. This is equivalent to making cheese from milk with less casein. The amount of casein reduction in the milk can be estimated.

Two methods are described for estimating yield losses. One uses a predictive yield formula to estimate yield from the control and casein-reduced milks. The other, preferred, method estimates an "effective", net, or economic reduction in yield. The latter standardizes the two milks to the same casein; fat ratio and accounts for the value of whey fat; the economic reduction must be qualified by the composition of the cheese, whey, and milk; by the name of the variety; and by the relative value of milk fat and cheese.

Key Words: milk-clotting enzymes • cheese yield • proteolysis

Submitted on November 6, 1989
Accepted on June 18, 1990