The use of soybean, in particular in forage production without preliminary heat treatment is not appropriate, and sometimes dangerous, because of the presence of antinutrients. As a marker in assessing safety of cakes and meals, there is often used urease in forage production. This paper describes the results of thermal inactivation of urease in soybean during the process of high-temperature micronization (heating of grain in the flux of infrared radiation). There have been obtained the empirical dependencies of the degree of its inactivation on time of heat treatment and energy exposure (the product of irradiation by the time of treatment). The similar dependences of urease activity on grain temperature are invariant to infrared heating (irradiation and time) regimes, but their nature is affected by the initial moisture content. The paper proposes the models of inactivation of antinutrients based on of the first-order equations of chemical kinetics with the reaction rate constant in various forms (Arrhenius and Hinshelwood, the transition state theory). The models have been tested on literature data on the inactivation of a trypsin inhibitor at a constant temperature. The models are further refined taking into account the variable (increasing) temperature and are reduced to the simplest form: Y = k [Exp (-ε R /T) -T 0 еxp (-ε R /T 0 )], where T, T 0are the current and initial temperatures of grain, k, ε R -the empirical coefficients. The identification of the model coefficients was carried out based on the results of inactivation of urease during heating in the flux of infrared radiation. It has been established that the results of thermal inactivation of soybean do not depend on the IR processing regimes and are determined only by the initial moisture content of grain, and by the end heating temperature. The efficiency of inactivation is higher the higher is the used irradiation. There is a compensating effect -with the growth in one coefficient, another is also increased. The considered models can be used for the thermal degradation processes and other thermolabile substances.

The paper dwells on the development of experimental dependencies of heating and dehydration of grain and cereals when varying the irradiance, ambient temperature in the heat treatment zone and the initial moisture content of product, and the development of the mathematical models for heating and dehydration of some grains and cereals. The grain was heated on the laboratory equipment with quartz halogen linear infrared emitters. The irradiance on the working surface in the treatment zone was determined by calculation using a specially developed program. The ambient temperature was determined by a thermocouple thermometer placed in a ceramic tube. The grain temperature was estimated as average by weight by a thermocouple thermometer after its transfer into a thermally insulated container. The following dependencies have been obtained: 1 -Temperature dependence of the heating time for different heating modes and initial moisture content. 2 -Dependence of moisture content on the heating time under different conditions and initial moisture content. 3 -Dependence of moisture content on a temperature under different conditions and constant initial humidity. The models of the heat-moisture exchange and dehydration processes have been created, and the model parameters K 0 and K T of the temperature dependence of some grains have been identified, as well as their dependence on moisture content and treatment modes has been evaluated. It has been established that this model describes adequately the process of dehydration to an extent limited by the upper temperature value of grain not much more than 100 ºС. Within not limited to the upper temperature value of grain not much more than 100 ºС. From the presented graphs (Figures 1.24 -1.26) and earlier obtained results for barley and millet, it can be assumed that the model describes adequately experimental data on the small-sized (3 -5 mm) objects.

The article presents the results of studies on the model systems of extrudates  conducted with a view to determining the function of moisture during the process of forming the structure of starch pastes. There was studied the influence of the moisture content of raw materials on a starch gelatinization point. Studies showed that 15% moisture content in raw materials is sufficient for its constituent phase – starch gelatinization, as well as for the transition of the whole mass to a fluid-viscous state. Further increase in the moisture content is accompanied by a decrease in a gelatinization point. In order to study the influence of moisture on the formation of a porous structure of extrudates, we studied the relationship between the different-type starch pastes and the degree of its transparency and its embrittlement temperature. It has been found that during the process of thermal and mechanical impacts, there occurs the process of the formation of a structure of starch pastes, in particular, samples with the different moisture contents can have an amorphous or crystalline structure. There has been established the relationship between the moisture content of raw materials on the modulus of elasticity of starch pastes based on them. The modulus of elasticity of samples was determined one hour (cooling time to room temperature) and one week after obtaining the starch paste. The above studies showed that minimal physico-chemical and mechanical transformations occur in starch pastes, which are in an amorphous state, that is, in the conditions of a low moisture content. We have established that the moisture content of raw materials, on the one hand, ensures the transition of a high-dispersive phase to a fluid state, or implementing the ex process of extrusion, and on the other hand, influences on the formation of a porous structure in the extrudates.

The article considers the change in chemical and biological characteristics in some legumes grains, under conditions of high-temperature micronization with different moisture contents during heat treatment with infrared rays. The heat treatment of grains was carried out on a laboratory apparatus with a quartz radiant infrared panel. The temperature variation in the heat treatment zone occurred due to changing the distance between the panel and the surface of grains. The grain temperature was determined using a laser thermometer, and with a timer. To determine chemical and biological characteristics, we used a special optical density metering device. We have studied: 1. The dependence of starch content on the temperature in the changing initial moisture content. We found that after 30 seconds of high-temperature micronization of, “Tsanava“ beans at a grain moisture content of 12.7%, the starch content in the grain increases from 39.65% to 40.12%, then gradually decreases, and at 18.3% moisture content, it increases from 38.71% to 41.2%, with a moisture content of 28.6% it increases from 37.36% to 42.42%. Similar processes are also observed for the beans “field red“ and “white lupine“; 2. The dependence of glucose content on the temperature in the changing initial moisture content. As the mass fraction of starch decreases, the percentage of sugar (in terms of the equivalent amount of glucose) at a moisture content of 12.7% at the initial stage increases from 1.36% to 1.46%, and then the percentage of sugar increases relatively quickly to 1.64%, at a moisture content of 18.3% it increases from 1.3% to 1.38%, and then increases to 1.51, with a moisture content of 28.6%, it increases from 1.28% to 1.35% and then increases to 1.54. Similar processes are also observed for the beans “field red“ and “white lupine“.

В статье рассматриваются две модели обезвоживания фасоли сортов «Цанава» и «Красная полевая» при комбинированном конвективном и радиационном (лучистом) нагреве. Зерна фасоли разных сортов различаются как геометрическими характеристиками, так и цветом. В качестве источника инфракрасного (ИК) излучения использовалась панель из галоген-кварцевых излучателей. Как следует из экспериментальных данных, влияние высоты установки излучателя и исходной влажности зерна существенно сказывается на температуре. Влияние расстояния от излучателя до монослоя зерна на конечную влажность очень слабое, а зависимость от исходной влажности близка к линейной. Учитывая, что в промышленных установках высота излучателей над транспортером не регулируется, высота излучателей над продуктом в условиях эксперимента рассматривалась как фиксированный параметр, приводящий к изменению температуры окружающей среды и облучению поверхности боба. Математические выражения для моделей основаны на физических представлениях о тепло-массообмене и теоретических концепциях, выдвинутых А.В. Лыковым. В результате решения системы дифференциальных уравнений относительно температуры и влажности им были получены решения в виде бесконечно убывающего экспоненциального ряда. Некоторые допущения позволили упростить выражения. В качестве независимых переменных в моделях использовались исходная влажность, время нагрева и температура поверхности зерна. По результатам проведенных экспериментов были идентифицированы коэффициенты моделей. После определения коэффициентов модели позволяют прогнозировать конечную влажность зерна с точностью около 2 %, контролируя время пребывания продукта в зоне обработки или его температуру на выходе.