Rennin-like Enzyme from Mucor pusillus for Cheese Manufacture

Abstract

A fungal rennet produced from Mucor pusillus is satisfactory for cheese manufacture. Enzyme stability in powder and in saline solution is excellent. However, severe activity losses occur when blended and stored with veal rennet in liquid form. Coagulation by fungal rennet is more sensitive to high pH than veal rennet, but less sensitive than swine pepsin. Coagulation by fungal rennet is more affected by Ca−- than veal rennet. Fungal rennet produces a greater nonprotein-nitrogen increase in casein solution and in cheese than pepsin or rennet. Higher lipase activity is also present, suggesting advantages in acceleration of curing. Normal clotting time and curd tension can be obtained through adjustment of: rennin units in coagulant, amount of Ca++ in milk, temperature or time of setting, or blending with veal rennet. Normal Brick, Cheddar, Pizza, and Parmesan cheeses have been made with fungal rennet. Solids losses in whey suggest careful control of factors affecting curd tension and use of a coagulant blend containing predominantly veal rennet. © 1967, American Dairy Science Association. All rights reserved.