Open AccessEngineering rheology in food industry
Author(s) -
Viktor Vladimirovich Kogan,
Larisa Eduardovna Semenova
Publication year - 2019
Publication title -
vestnik astrahanskogo gosudarstvennogo tehničeskogo universiteta. seriâ: rybnoe hozâjstvo
Language(s) - English
Resource type - Journals
eISSN - 2309-978X
pISSN - 2073-5529
DOI - 10.24143/2073-5529-2019-4-147-156
Subject(s) - rheology , materials science , raw material , shear rate , viscoelasticity , shearing (physics) , composite material , viscometer , viscosity , chemistry , organic chemistry
The paper describes the technological processes of the food industry assuring production of a finished product with predetermined properties, where different types of food raw materials and semi-finished products are objects of study of engineering rheology, considering their be-havior at the stage of deformation (compression, twisting, stretching). The processes of mixing and inter-operational transportation of products are interrelated with the viscous-plastic raw materials (dough, minced meat, candy mass) contacting with the working parts of machines. That is why, in order to rationally use and save material resources the selection of process parameters and operating modes should be carried out subject to the rheological properties of the products (shearing, surface, volumetric). These properties have been listed and their nature has been described. The basic shearing characteristics of the raw materials under study have been determined and analyzed. Specific features of the elastic, viscous and plastic properties of the product under stress are considered. The combinations of rheological models of simple idealized bodies are studied: viscous-plastic, elastic-plastic. Equations that describe the flow of various viscous-plastic media are given. The dependence of the effective viscosity on the stress or shear rate for meatball meat from fish is graphically presented. The effect of minced meat humidity on the structural and mechanical properties of meatballs from fresh carp, pike, catfish, and bream has been traced. Rheological characteristics were determined by a rotational viscometer RV-8. Samples were prepared for one specimen from each product by adding a different amount of water, followed by stirring and thermostating. In parallel, the fat content was determined. According to the obtained values of structural and mechanical characteristics, the rheological properties of meatballs have been illustrated in a wide range of variables. From the data obtained it can be inferred that with increasing humidity, the numerical values of all shearing characteristics decrease due to thickening of the liquid interlayers between the product particles, and the rate of the mechanical structure remains practically unchanged.