Proteolytic Enzymes in Human and Cow's Milk

Abstract

The presence of proteolytic enzymes in milk was measured by analyzing for liberated tyrosine while the milk was held at 100[degree]F for periods up to 6 hours. Bacterial growth was effectively controlled by the use of a mixture of the antibiotics, bacitracin and polymyxin B. Human milk and enzyme-treated milk (Enzylac) contained substantially equal amounts of proteolytic enzymes. Raw or pasteurized cow''s milk contains about one-fifth as much proteolytic enzymes as either raw human milk or pasteurized enzyme-treated cow''s milk. The implications of these findings are discussed.