Five types of cereals (wheat, covered barley, naked barley, covered oats and naked oats) were extruded for 6, 6.5, 7.6, 8.2, 9.1 and 10 seconds with subsequent control of the water and the protein content. The water content statistically significantly (p < 0.001) decreased during all the processing time with the final values of 7.3 %, 6.3 %, 7.2 %, 6.0 % and 6.5 % for wheat, covered barley, naked barley, covered oats and naked oats respectively. The protein content slightly decreased during all the processing time with the final values of 11.51 %, 10.95 %, 14.10 %, 13.01 % and 13.10 % for wheat, covered barley, naked barley, covered oats and naked oats respectively. The effect of processing time on the water content can be modeled by polynomial regression whereas the effect of processing time on the protein content can be modeled by linear regression.

The research on the influence of extrusion time in obtaining textured products from extruded wheat, barley and oats was based on the study and determination of optimal extrusion modes that affect the fat content and ash content in extrudates. Texturates obtained from extruded grains of wheat, barley and oats were taken as objects of research. Covariance analysis using time as a quantitative factor and the type of grain raw materials as a qualitative factor confirmed that both the transit time (p<0.001) and the type of raw materials (p<0.001) affect the fat content and ash content. Post-hoc tests (Duncan's test and Fisher's test) showed that all types of raw materials differ statistically significantly (p<0.001) in ash content during extrusion, except for variants of naked forms of barley and oats, statistically significant differences between which were not revealed. With an increase in the extrusion time, there is a decrease in the fat index in the extrudates of the main grain crops. The increase in the time spent by the grain in the extruder does not actually affect the change in the ash content, the ash content in the extrudates of grain crops changes slightly. The conducted studies allowed us to determine the extrusion time for each type of grain crops, at which the quality indicators improve. Thus, the optimal extrusion time for wheat and filmy barley is 9.1 seconds, naked barley 7.6, filmy oats 8.2, naked oats 6.3.