COMPLEX STUDIES OF CULTIVATION PROCESS OF BAKER’S YEAST WITH HIGH CONCENTRATIONS OF BIO-MASS. 1. INVESTIGATION OF PHYSICAL PROPERTIES OF BEET MOLASSES

doi: 10.25712/ASTU.2072-8921.2021.03.006

Abstract

The ways of increasing the efficiency of yeast factories are considered. The possibility and efficiency of the process of cultivation of baker's yeast at high concentrations of biomass up to 500 kg / m³ in a shell-and-tube jet-injection fermenter are shown. Comparison of technical and economic indicators of the cultivation process by traditional and proposed methods is given. The relationship between the coefficients of molecular transfer of momentum, heat and mass, namely, the coefficient of kinematic viscosity, the coefficient of thermal diffusivity, and the coefficient of molecular diffusion is presented. The analysis of the data published in the scientific and technical literature on the complex study of the dynamic viscosity of aqueous solutions of molasses in the case of using the cultivation of yeast at a high concentration of biomass was carried out. The purpose of this work is to conduct a comprehensive study of the physical properties of an aqueous solution of molasses for the selected range of temperatures and concentrations. The paper presents the results of experimental studies of the dynamic viscosity coefficient, which make it possible to trace the nature of the flow of aqueous molasses solutions at different contents of dry substances in the temperature range of 10-70 ºС and in the shear rate range of 1-500 s-1, and their graphical dependences. Processing of experimental data obtained by measuring the viscosity of molasses solutions using a Rheotest RN 4.1 viscometer. and the Heppler viscometer, made it possible to determine the numerical values of the dynamic viscosity coefficients and their mathematical interpretation depending on the concentration of dry substances at different temperatures. The values obtained with these devices allowed us to assume that, as a result of the experiment, the devices give similar, and, therefore, reliable results.