The study objects were the Republic of Kazakhstan selection apple sorts: “Baiterek”, “Sarkyt” and “Saya”, also pear sorts: “Syilyk”, “Zhazdyk” and “Nagima”. Study of the process of moisture evaporation within vacuum drying of the fruits has essential value in the nutritional value saving. Basically, the product evaporative capacity is characterized by the evaporation resistance coefficient ‒ µ. Also during moisture removal, thermodynamic state of moisture changes that is described by water activity indicator ‒ aw. Experimental determination of these parameters allows for the analyzing moisture evaporation during vacuum drying process. Studies have established the following evaporation resistance coefficients: µ=2.03±0.07 for apple sorts and µ=2.3±0.05 for pear sorts. Either water activity decreases from 1.0 to 0.62±0.01 for apple sorts and from 1.0 to 0.65±0.04 for pear sorts. Two drying periods are discovered. The first drying period: 5.45–6.10 h for apple sorts; and 6.12–6.25 h. for pear sorts. The second drying period duration: 4.15–3.50 h for apple sorts; and 4.35–4.48 h for pear sorts. The critical humidity value: 27.1±2.1 % for apple sorts; and 30.1±2.5 % for pear sorts. Comparative analysis of calculated and experimental data shows maximum deviations 22.5 % for apple sorts and 23 % for pear sorts. The proposed equation for the calculating a moisture evaporation rate, considering the product properties and the hygroscopic parameters of air, can be used in practice to study the moisture evaporation dynamics from the product surface. The study results allow for the selecting an optimal mode for vacuum drying of apples and pears sorts in order to safe nutritional value and to produce biologically active additives for the food industry

The fermented mare's milk -Koumiss and camel's milk -Shubat are traditional national dairy products in Kazakh cuisine. Concentrated dairy products in the form of clots have a quantity content of useful chemical compounds. In the presented study it was investigated the desorption isotherms of the koumiss and shubat clots enriched by vegetative additives. It was established, that the interface between weakly and strongly bound moisture can be: for the koumiss clots enriched by juices: of a carrot а w =0,56, u х = 0.69 kg/kg; of a pumpkin а w =0,58, u х = 0,80 kg/kg; of a beet а w =0,59, u х = 0,81 kg/kg; as well as for shubat clot, enriched by juices: of a carrot а w =0,62, u х =0,73 kg/kg; of a pumpkin а w =0,65, u х = 0,67 kg/kg and of a beet а w =0,63, u х =0.66 kg/kg.

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As the drying zone deepens, outer surface layer of the product does not have time to be moistened, due to a small amount of moisture coming from the inside. It becomes dry, its temperature rises. The intensity of moisture transfer from the inner layers of the product depends on many parameters, including a moisture diffusion coefficient. The study aim is to create a methodology for determining the moisture diffusion coefficient within vacuum drying of fruits, by taking into account cracks, channels and capillaries formed in the dry layer of the product through the resistance coefficient to evaporation. The work essence consists in the determining of the moisture diffusion coefficient as a driving force, a difference between water activity and air humidity, by considering the resistance coefficient to evaporation, characterizing the effect of hydrodynamic resistance of the dried dry layer of the product. This approach was used to determine the moisture diffusion coefficient during vacuum drying of the Baiterek apple sort and the Zhazdyk pear sort of Kazakhstani selection. It was established that in the first period of drying the moisture diffusion coefficient decreases on average from 24,4∙10‒7 m2/s to 13,2∙10‒7 m2/s. The critical humidity for pear is 37.4 %, and for apple 35.1 %. As result of the formation of dry layer on the surface and subsequent layers, the moisture diffusion coefficient gradually decreases. In the second drying period, the moisture diffusion coefficient decreases from 5,42∙10-8 m2/s to 2,12∙10‒8 m2/s. The work practical significance is related with the application of the obtained results in the determination of the optimal drying regime with maximum preservation of the product original quality. The proposed methodology can be used in the practice to study the moisture diffusion coefficient within vacuum drying of fruits, by considering the product properties and the hygroscopic parameters of the drying matter

This work is aimed at developing a procedure for controlling the rheological properties of wheat dough during its kneading based on a parametric model. Dough kneading is the most important technological operation in the production of bakery products. When organoleptically assessing the consistency of the dough, it is difficult to accurately determine its rheological properties while maintaining the mass of water and its intensity at a constant level of the mass of the kneaded dough, considering the processed flour. However, our proposed procedure can solve these problems. According to the results obtained, it was experimentally found that the nature of changes in the specific intensity of dough kneading, which contributed to obtaining the best quality bread at a kneading body rotational speed of 150 rpm, is optimal. The dough kneading intensity leads to a reduction in the kneading time from 290 s at nm=60 rpm to 90 s at nm=240 rpm. The optimal duration of dough kneading  was 124 s. The results make it possible to determine the water absorption capacity of flour in the production of bakery products, considering its baking properties and dough recipe, and, accordingly, the optimal moisture content of the dough