VARIATION IN COMPOSITION AND FUNCTIONAL-PROPERTIES WITHIN BRINE-SALTED MOZZARELLA CHEESE

Objectives of this research were to determine whether locational differences in composition within a cheese block affected melting characteristics. Immediately after brining, industrial low moisture and low moisture, part skim cheeses were divided in half vertically. Equally weighted samples representing surface and center from one-half of each block were analyzed immediately (d 2) for apparent viscosity, free oil, and composition (moisture, fat, NaCl, Ca, pH). Samples from the other half were vacuum packaged and stored at 4-degrees-C until analysis on d 16. From d 2 to d 16, free oil increased significantly, and apparent viscosity decreased significantly. Free oil increased the most in the center of low moisture cheeses, indicating that Mozzarella with high fat and low NaCl contents has greater tendency to oil off. Surface samples had significantly higher NaCl and apparent viscosity and lower moisture, Ca, and free oil than center samples. These locational differences in melting characteristics may be caused in part by exchange of Na with casein-bound Ca at the cheese surface, which enhances the emulsifying ability of soluble casein, resulting in a more emulsified fat phase at the cheese surface and less formation of free oil.