Lipase in milk, curd and cheese

Presence of lipase in milk, curd, whey and cheese was studied. A small amount of the product was added to a large volume of lipase-free whole milk that had been made sensitive to lipolysis by homogenization. Increase of the acidity of the fat in the mixture, determined after incubation, was interpreted as enzyme activity being present in the product concerned. Results obtained in this way showed that lipase was present in raw milk and in the curd and whey made of it, but that the bulk of the enzyme disappeared quickly from the curd during Gouda cheese making, as a result of several factors including scalding of the curd, whey removal and pH decrease. By using this method no lipase could be detected in ripened Gouda cheese, made of raw milk. Furthermore, no potential lipolytic activity was measured in ripened danish blue cheese, but it was in ripened Camembert and Brie, all of these cheeses being made of pasteurized milk. Obviously, the presence of active milk lipase in ripening cheese is by no means self-evident.