RHEOLOGICAL EVALUATION OF MOZZARELLA CHEESE BY UNIAXIAL HORIZONTAL EXTENSION

Rheological properties of low-moisture part-skim Mozarella cheese were evaluated as a function of storage time, test temperature, and deform ation rate by uniaxial extension in a horizontal plane. Proteolysis of Mozzarella cheese caused marked decreases in the tensile strength and the deformability modulus, but not in the fracture strain. As the tem perature increased from 10 to 40C, the fracture strain increased more than five-fold. The strength and the deformability modulus decreased a bout 60 and 85%, respectively, as the cheese temperature increased fro m 10 to 30C The fracture strain of the cheese did not exhibit a clear trend with the deformation rate in the range of 50-500 mm/min. However , its strength and deformability modulus increased with the increasing deformation rate.