Effect of Thermal Treatment on Physicochemical, Structural, and Mechanical Properties of Natural Cheese

Abstract

The article describes the changes in the physicochemical and rheological parameters of various natural cheeses after their thermomechanical processing. The experimental heat-treated cheeses consisted of natural cheese, citrate-phosphate emulsifying salt, and water. The test parameters involved mass fraction of moisture and fat, active acidity, elastic modulus, dynamic viscosity, and tg δ, i.e., the loss vs. elastic modulus ratio. All these indicators affected the functional properties of the resulting pizza cheeses. Citrate-phosphate emulsifying salts increased the buffer capacity and stabilized the active acidity of the heat-treated cheeses relative to the natural cheese samples, blue cheeses and cheddared cheese masses being the only exceptions. Emulsifying salts and water reduced the fat content. The thermal treatment also lowered such indicators as elastic modulus, dynamic viscosity, and tg δ, which affected the consistency of the final product. After the thermomechanical processing, the natural cheeses became less dense but more elastic, plastic, and loose. Their physicochemical and rheological characteristics changed, which means that the thermal treatment gave the resulting heat-treated pizza cheeses some functionally useful properties.