At the beginning of the third millennium, improving the people's standard of living has become a top priority in the development of the human community. Agricultural lands play a crucial role in this process. Their rational involvement in economic circulation and comprehensive use create the necessary organizational, economic, social, and legal conditions for ensuring food security and sustainable development in Russia. This article explores the governmental and market mechanisms for involving agricultural lands in economic circulation and their comprehensive use.
The process of heating meat products during their baking can be described based on the application of the theory of non-stationary thermal conductivity. However, when determining the Fourier and Biot similarity numbers, the problem of taking into account the variability of the thermophysical characteristics (TPC) of biological material arises. The change in the thermal and physical characteristics of meat products during heating occurs according to complex laws, which is caused by the thermal effects of phase and physicochemical changes. Based on the theoretical studies, a method for determining the equivalent Fourier and Biot numbers is proposed, taking into account the combined change in the thermal and physical characteristics of the surface and internal layers of meat products during baking. The authors conducted experimental studies to evaluate the effectiveness of the proposed method. Samples of minced meat with different fat-to-moisture content ratios (wet skimmed and low-moisture fatty) were selected as objects of study. The samples were formed in the form of bodies of canonical shapes – one-dimensional plates and cylinders. Heat treatment was carried out in a convection apparatus with direct contact of the product with heated air, which was achieved by using rod cassettes. Equivalent values of thermal conductivity were calculated for the selected materials. The results of the experimental studies were presented in the form of graphical dependencies Θ = f (Fo) using equivalent and variable values of thermophysical characteristics on temperature. The obtained curves form practically straight lines for both variants of accounting for TPC, characteristic of the regular mode of non-stationary thermal conductivity. Comparison of the data shows that when using equivalent values of the TPC, the convergence of the experimental points is higher than when using variable values of the TPC.
The traditional pectin production technology is highly energy-intensive and environmentally unsafe. One of the possible ways to improve the technological process of pectin production is to dry directly the petine hydrolyzate before it is precipitated with ethyl alcohol. The most effective method of drying pectin hydrolyzate is drying in a vibrofluidized layer of an inert material, which provides high productivity in terms of evaporated moisture per unit volume of the chamber and the quality of the resulting dry product. This paper proposes a method for optimizing the drying process of pectin hydrolyzate in the apparatus of a vibrofluidized layer of an inert material, which makes it possible to determine the values of regime parame-ters at which the drying process proceeds with minimal costs for thermal and electrical energy. The technique is based on the experi-mentally obtained relationship between the specific productivity of the drying unit and the following operating parameters of the drying process: the air velocity in the drying chamber, the initial air temperature, the specific load related to the area of the gas distri-bution grid, the initial concentration for dry substances. On the basis of this experimental dependence, the criteria for assessing the reduced costs for heat and electric energy are formalized. A complex criterion for optimizing the drying process in a vibrofluidized bed is formulated, the minimization of which makes it possible to increase the efficiency of the drying process. Restrictions on the ranges of variation of the operating parameters of the drying process are formulated as well. The posed problem of optimization of the drying process in a vibrofluidized bed is solved numerically using the method of sequential quadratic programming and recom-mendations are formulated on the values of operating parameters for conducting the process in the optimal mode.
An experimental study has been made of the density and the velocity of sound for liquid decalin and cyclohexane in the range of temperatures 298.15–433.15 K and pressures 0.1–100.1 MPa. Parameters of equations have been obtained that describe the dependences of the specific volume of liquid decalin and cyclohexane on their temperature and pressure and of the isobaric heat of these substances on their temperature at atmospheric pressure. The density, the velocity of sound, the isobaric and isochoric heats, the isobaric expansion coefficient, and the coefficients of isentropic and isothermal compressibilities of liquid decalin and cyclohexane have been determined in the range of temperatures 298.15–433.15 K at pressures to 100 MPa.
The article reflects the possibilities of using the descriptor-profile method in modeling recipes of functional food products taking into account the consumer preferences. Preserved foods using sprouted bare-grained oats or wheat and barley-malt extract served as samples for research. The simulation of the consumer preferences of the preserved product was carried out using a descriptor-profile method of tasting analysis. There were thirty-two features of descriptors identified for assessing organoleptic indicators and emotional customers’ perception of the product. A visual model of the consumer preferences of the preserved product was formed. The intensity and significance of each descriptor were determined. Influence of share of sprouted grain and malt extract on consumer preferences of preserved product was studied. Increasing the share of sprouted grain in the product reduced the coverage of the grain with the extract, the pallor and hardness of the grain, the intensity of brown color and the presence of malt-apple aroma. An "ideal" portrait of the product has been developed taking into account the strengths and weaknesses of the product, allowing to design organoleptic indicators at the stage of product development. High consumer preferences of the preserved product – a harmonious sweet taste with slight sourness, malt-apple-honey aroma, moderate grain hardness, lack of bitterness, – were achieved with 40% – 50% sprouted grain and 50% – 60% extract.
