Lipase Activity during Making and Ripening of Cheddar Cheese

Abstract

The stability and pH activity characteristics of milk lipase are such that this enzyme can play no continuing role in the ripening of Cheddar cheese after making. Analyses made at intervals during the making and ripening of raw milk Cheddar cheese show that milk lipase disappears during the making and is completely absent in the young cheese. The addition of rennet extract during Cheddar cheesemaking causes an increase in lipolytic activity. This increase in lipolytic activity disappears within a period of approximately 30 minutes. After 5 to 20 days, lipases which are considered bacterial begin to make their appearance in the young Cheddar cheese. Most of the lipase active at pH 5 is set free between the fifth and hundredth day of ripening. Lipolytic activity in pasteurized milk Cheddar cheese can be detected in larger amounts between the fifth and twenty-fifth day of the ripening period than in corresponding raw milk Cheddar cheese. At any time after the cheese is 30 days of age, however, the total lipolytic activity of pasteurized milk cheese is less than half that of corresponding raw milk cheese. Bacterial lipases are believed to be at least in part responsible for more rapid flavor development in raw milk Cheddar cheese as compared to Cheddar cheese made from identical milk after pasteurization. © 1948, American Dairy Science Association. All rights reserved.