Mechanical Processing of Food Using Physical Properties Change by Temperature Control

Abstract

In general, raw materials used in food processing are comprised of complex tissues. The chemical composition (e.g. moisture, protein content, lipid content) of each type of tissue varies depending on the tissue’s biological function. These differences in chemical composition determine the mechanical properties of each material and affect their temperature dependence. Hence, by understanding the temperature dependence of the mechanical properties of the tissues found in the raw food material, and then devising the optimal temperature and method for processing, materials which cannot be prepared by conventional methods may be mechanically processed with comparative ease. The authors examined new food processing technologies which facilitate the mechanical processing of food materials by controlling their temperature, and which can adjust the mechanical properties (e.g. fracture stress, elastic modulus, Poisson’s ratio, brittle temperature) of various tissues in the food material, in order to create the best state for processing. In this paper, a mechanical processing method which actively takes advantage of the changes in the mechanical properties of the food material according to the tissue’s temperature dependence is introduced.