Commercial Cold-Pack Cheese Food which exhibited marked syneresis in consumer packages had a pH of 4.60 to 4.80. Bi-weekly microbial examination of commercial Cold-Pack Cheese Food stored at 5, 10, 15, and 20 C indicated a marked growth of lactobacilli and streptococci at all temperatures above 5 C and a slight decease in staphylococci at all temperatures. It is assumed that the lactose added in the form of skim-milk or whey powders provided the carbohydrate nutrient source for these organisms so that the pH was reduced from 5.05 to 4.60, The minimum hydration of casein occurs at pH 4.60 and this lowered pH caused syneresis in the packages. Cooling the Cold-Pack Cheese Food quickly to 5 C and keeping it at or below this temperature eliminated the problem.

This content is only available as a PDF.