Okara - soybean residue, a product obtained from the production of soy milk. It is also a valuable food product, contains a lot of fiber and protein. However, when consumed in food, a raw soybean residue is undesirable due to the presence of enzyme inhibitors and an unpleasant «fish» and «bean» taste. Therefore, the remainder of soybeans must be subjected to heat treatment before being included in various food products. To obtain an extrudate based on corn and okara, a mixture of corn grits and flour from okara was extruded using a single screw extruder. Statistical processing of the experiment was performed using the response surface plan. As independent factors, such factors of influence on the extrusion parameters were used as: screw speed (350-450 rpm), the content of soybean residue in the mixture (20-40%) and the humidity of the mixture (14-18%). The following variables were considered as dependent variables: water absorption index (WAI), water solubility index (WSI) and hardness (H). The results of the study showed that the most significant variables are the content of soybean residue, which has a positive effect on hardness, and the screw speed, which has a positive effect on hardness, while the moisture content of the mixture is insignificant in most characteristics.

The article presents material indicating the possibility of using thermal vacuum extrusion for the purpose of disinfection of food waste. A design and technological scheme of one of the variants of the technical solution of the proposed method is proposed. Arguments are given for further improvement of thermoplastic extrusion in order to increase the energy efficiency of the process.

The article investigated the influence of screw configuration (4:1 and 1:1), moisture content (15% and 20%) and particle size of corn grits on the properties of extrudates. Samples were extruded in a laboratory single screw extruder, at a temperature of 135/170 °C, using a die of a matrix with a diameter of 4 mm. The physical and rheological properties, digestibility and starch damage of the obtained extrudates were determined, then the results were compared with control samples of non-extruded corn grits. Lower moisture content and the use of a screw with a compression ratio of 4: 1 increase the degree of expansion and destructibility, but reduce the bulk density and hardness of the extrudates, regardless of grain size. After the extrusion process, the water absorption index increased, but the peak, hot and cold viscosity of all samples decreased, with a more pronounced effect in cereals extruded with a lower moisture content and with a 4:1 screw. Extrusion caused a decrease in the content of resistant starch and an increase in starch damage in all samples.

The article examines the dependence of the specific mechanical energy and physical properties of barley extrudates (expansion coefficient, bulk density and hardness) on the adjustable parameters of extrusion processing (temperature at the exit from the die 120-150 ° C, raw material moisture 20-24% and screw rotation speed 260- 340 rpm). The response surface methodology was used as a statistical method. A second-order polynomial regression model was used as a model for fitting experimental data. The temperature at the outlet of the die and the moisture content of the raw materials, as well as the interaction between them, were the factors that most influenced the characteristics of the product. A significant correlation was found between hardness and bulk density, hardness and expansion coefficient, bulk density and expansion coefficient for barley extrudates. High temperature at the die outlet, low humidity and medium to high screw speed were determined to be optimal characteristics.

The article discusses the influence of the moisture content of raw materials and the temperature of the extruder die on the engine torque and specific mechanical energy. An EK-40 laboratory extruder and a slot die / rheometer combination were used to measure the torque. The torque decreased with increasing humidity and temperature of the die. It was found that the temperature of the matrix is the most significant parameter affecting the torque and specific mechanical energy.

This study evaluated the effect of extrusion processing on the specific mechanical energy and physical properties of chickpea extrudates (expansion coefficient, bulk density and hardness). The experimental data were processed using the response surface methodology with the following parameters: temperature at the exit from the die (120-150 °C), humidity (20-24 %), and screw rotation speed (260-340 rpm). The factors that most influenced product performance were die outlet temperature and feed moisture content, and the interactions between them. A significant correlation was found between hardness and bulk density (positive), hardness and expansion coefficient (negative), and bulk density and expansion coefficient (negative). The desired characteristics (high expansion, low bulk density and hardness) for the chickpea were obtained at a high die outlet temperature, relatively high humidity and a high screw speed.

The influence of the operating conditions of the extruder (raw material moisture, die temperature, screw speed and mass flow rate) on the pressure drop in the die for wet raw materials was investigated. An EK-40 laboratory extruder and a slot die / rheometer combination were used to measure the pressure drop across the die. The pressure drop decreased with increasing humidity, screw speed, and die temperature, and increased with increasing mass flow. It was found that the temperature of the matrix is the most significant parameter affecting the pressure drop of the matrix.

The article provides a study of factors (screw speed and mass flow rate) affecting the operating conditions of the extruder, engine torque and specific mechanical energy for high-moisture raw materials. A laboratory extruder and a slotted die with a rheometer were used to measure the die torque. The die torque decreased with increasing screw rotation speed and increased with increasing mass flow. However, the increase in mass flow has led to a decrease in the specific mechanical energy. Increasing the screw speed increased the specific mechanical energy. This was due to the higher shear rates at higher screw speeds.