Effects of small concentrations of Mucor miehei protease on stability of sterile milk-based dietetic foods.
Four commercial sterile milk-based dietetic products were inoculated aseptically with small concentrations of a commericial milk clotting enzyme derived from Mucor miehei and incubated at 30 C for 32 wk. One of the products, Sustacal, exhibited no observable changes in body and texture during storage. Enzyme concentrations of 1 x 10(-4) chymosin units per milliliter or higher induced undesirable changes in the body of the other three products, Enfamil Ready-to-Use, Enfamil Concentrate, and Metrecal Shape. None of the products was affected visibly by enzyme concentrations of 1 x 10(-5) chymosin units per milliliter or less. In-can sterilization of Enfamil Ready-to-Use at 126.1 C for 4.5 min and Enfamil Concentrate at 126.7 C for 4.23 min completely destroyed all measurable enzyme activity at concentrations (up to 5.5 x 10(-2) chymosin units per milliliter) in these experiments. However, 1 to 3 h between formulation and sterilization allowed time for the enzyme at concentrations of 1 x 10(-2) chymosin units per milliliter or more to cause coagulation during heat sterilization.
D003611:Dairy Products; D004032:Diet; D005502:Food; D007225:Infant Food; D009089:Mucor / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000378:metabolism*; D013242:Sterilization
D010447:Peptide Hydrolases