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The development of food, biotechnological, and processing industries, the invention of new ingredients, optimisation and improvement of technological processes require reliable information about the main thermophysical characteristics of raw materials and materials of biological origin. This paper presents the results of the cooperation of specialists from leading universities and scientific institutions of Ukraine, embodied in the developed methods of analysing the parameters of thermodynamic and mass transfer processes and determining the thermophysical characteristics of the latest substances and products using modern metrologically certified devices and information-measurement systems. The main problem in analysing materials of biological origin is the inhomogeneity and heterogeneity of the structure of samples. It is demonstrated that it is advisable to determine the coefficient of effective thermal conductivity of bulk materials and cereals in a stationary thermal mode on a device for determining the thermophysical characteristics of materials and thermal effects, equipped with heat flow and temperature sensors, in which a symmetric scheme of the thermometric measurement method is implemented. The simultaneous use of four measuring cells allows for performing a synchronous comparative analysis of several samples, and the rotary-clamping mechanism helps to minimise contact resistances. The developed method of measuring the coefficient of effective thermal conductivity considers the features of bulk food products and substantially improves the accuracy of the examination by introducing a correction for the contact resistance of the wall layer. Long-term observations allow for analysing thermolabile materials, examining thermal effects in samples, and evaluating volumetric and integral heat generation. It is necessary to use the STA system to conduct calorimetric studies of a wide range of biological materials and substances with the necessary accuracy, which implements methods of step-by-step scanning and synchronous thermal analysis to determine the specific heat capacity, the heat of evaporation, and the ratio of free and bound moisture in nonhomogenous materials. These characteristics are necessary parameters for analysing the kinetics and optimisation of heat and mass transfer processes, in particular, drying, in the calculation and design of technological equipment. [ABSTRACT FROM AUTHOR]

The effect of mechanical action on the mixing and whipping of a mixture of components contributes to the establishment of a three-dimensional sponge-mesh continuous structure of the gluten framework, as it determines the elastic and elastic properties of the medium and is relevant in the dispersion of gas in a liquid. The purpose of the work was to establish the relationship between the gas retention capacity of the medium and the energy consumed for the hydration of the components. The experiments performed the task of determining the gas retention capacity of the medium with variable parameters of the height of the liquid phase from the intensity of mixing, the time of the transient processes of the formation of the full volume of the gas-liquid medium, the time of the transient process of the dispersed gas phase. The difference in levels before the gas phase generation and the stirring mode determines the value of gas retention capacity. Therefore, it was concluded that it is expedient to completely destabilise the steady-state regimes by changing the modes of action of the working body in the flow system. An additional impact on the system is the change of hydrodynamic regimes due to the unstable dynamics of the dispersed gas phase generation. The generation of this phase means the presence of energy costs for the interfacial surface establishment, which must be considered in the overall energy balance. In addition, a part of the gas phase, which existed and continues to exist in the new regime after mixing, enters the transient regime. Therefore, the most effective mixing occurs in case of compliance with the shifted mode of dosing components in a suspended state and the mechanical impact of the working body. Considering the tasks and conditions for mixing the dough, the requirements for the design of the mixer are determined, and it is established that the supply of components should last at least 45 seconds. During this period, there is hydration and a reduction in energy consumption. Such an approach intensifies mass transfer and biochemical processes under conditions of thermodynamic equilibrium with appropriate desorption bonds of the dissolved part of the gas phase and liquid, which covers a new method of mixing and allows further use in the design calculations of working chambers [ABSTRACT FROM AUTHOR]

Evaluation of the influence of amplitude-frequency and power parameters of external technological action on bulk products in the process of separation of the impact, the way of lowfrequency oscillations of the working bodies of the separator and the angle of inclination of the container during processing determines the main indicators of technical and economic efficiency of the explored process, which is the relevance of the research. The purpose of the study is to substantiate the operating parameters of the explored separator of volume vibrations by determining the patterns of change in the kinematic and power characteristics of the vibration drive. To determine the rational parameters of the vibration screening process, the equations of motion of the working bodies in the form of a conical sieve surface were obtained using the method of Lagrange equations of the 2nd kind. Using the solution of the Cauchy problem for linear inhomogeneous differential equations, the solution of the latter was obtained. Using the Math CAD mathematical environment, the dependences of the amplitude of oscillations, vibration velocity and vibration acceleration, and the intensity of oscillatory motion were obtained, which allowed performing a mathematical analysis of the power and energy characteristics of the vibration drive of the explored separator. The main effects of the developed design of the vibrating separator are an increase in the driving force of the process of separation of bulk solids in this work, which was achieved by providing the working cylindrically-conical container with vibratory motion; improvement of the conditions for the passage of product particles through the perforations, which was achieved by providing the sieve surface with volumetric vibrations; reduction of energy consumption and improvement of the operating conditions of the supporting units during the operation of the designed vibrating screen, which was achieved by installing additional elastic elements between the separator body The inclined arrangement of the conical sieve surface allows for spatial gyratory or circular translational motion, which allows implementing of the advantages of bulk separation of bulk solids. The results of the analytical study allowed substantiation of the optimal angle of inclination of the working sieve surface. Based on the analysis, the design parameters of the vibration exciter were substantiated and specified and the design of this technical system was presented. The practical value of the conducted research can be attributed to using the designed kinematic combined vibration exciter of volumetric oscillations in the separator, which allows reducing the weight of the oscillating parts of the drive and, accordingly, the energy consumption for the separation process [ABSTRACT FROM AUTHOR]