Studies of mild lipase

The processes involved in Cheddar cheese ripening are a mystery into which light is slowly being cast. It is generally accepted that raw milk cheese is ripened by enzymes native to the cheese milk and by microorganisms accidentally or purposely incorporated into the cheese. Pasteurization of milk for cheesemaking is a practice coming into wide acceptance and certainly has its merits. But the heat treatment of pasteurization inactivates many desirable microorganisms and destroys milk enzymes which could be important in cheese ripening. Pasteurized milk cheese could be made equal to the finest raw milk cheese if the agents responsible for flavor and body development in the aging cheese, which are destroyed by the heat treatment, could be added back to the milk after pasteurization. One of the agents destroyed by pasteurization is the lipolytic enzymes. It has long been believed that fat hydrolysis by a milk lipase was one phase of Cheddar cheese ripening. Therefore, it seemed desirable to investigate the lipase (or lipases) in milk which might be related to Cheddar cheese ripening.