Milk-Clotting Activity of Proteolytic Enzymes

Abstract

Most of the proteolytic enzymes coagulate milk, but in most cases no stable cheese is formed, as the coagulum is further digested by continued proteolysis. Rennin is distinguished by the practical limitation of its proteolytic action to specific cheese-forming hydrolysis. Trypsin and ficin are very active and typical for most of the proteolytic enzymes. Coagulating milk, these enzymes digest also the precipitated caseins. By reducing their activity some of them could be made stable cheese-producing enzymes. The following enzymes and enzymatic preparations have been comparatively studied as to the relation between milk coagulation and their proteolytic activity: rennin, pepsin, trypsin, pancreatin, chymotrypsin, papain, ficin, bromelain, takadiastase, and extracts of Israeli pumpkin, melon, grapefruit, and French artichoke and extracts of Japanese koji. This study enabled the authors to prepare vegetable rennet substitutes for cheeses of Cheddar-type processing, which after ripening possess flavor, body, and texture comparable to those made with animal rennet. © 1969, American Dairy Science Association. All rights reserved.