THE RESEARCH OF THERMOPHYSICAL AND RHEOLOGICAL PROPERTIES OF EDIBLE VEGETABLE OILS

doi: 10.25712/ASTU.2072-8921.2021.02.005

Abstract

In the food industry, the study of the thermophysical properties of edible vegetable oils is relevant for product quality control. The objects of research are edible oils: sunflower, mustard, linseed, camelina, rapeseed, milk thistle. The experimental data was obtained at the accredited laboratory of the Orekhovo-Zuevsky branch of the Federal State Budgetary Institution Rostest-Moscow. А Cossfield RT-1394H device was used in a different temperature range: from 20 to 120 ºC to determine the dependence of thermophysical characteristics and density of viscoelastic fluids. Thermophy­sical and rheological properties were measured: thermal conductivity, thermal diffusivity, mass specific heat, dynamic viscosity depending on temperature for the studied types of oils. During the experiment, it was found that the values of the thermal diffusivity and thermal conductivity coefficients are close. At the same time, a decrease in the values of the coefficients in the investigated temperature range was observed. The results in terms of specific heat capacity depend on the chemical composition, moisture content, structure of oils and the type of water bond. Based on the Lab View 7.0 software, the measured values were statistically processed and equations with approximation coefficients were obtained. This work evaluated the dynamic viscosity: the behavior of edible oils as a function of temperature. It was found that with an increase in the temperature of the studied edible oils, the dynamic viscosity decreases. The dependences for the studied oils were obtained, which obey the Arrhenius equation. The equations and the approximation value were determined. The analyzed experimental data will make it possible to determine criterion dependencies for thermal processes and establish hydrodynamic characteristics for production in the food industry.