One of the most common methods of preserving apple pomace in order to further obtain products with a high content of biologically active substances is drying. For the experiment, a method of drying with superheated steam of reduced pressure in a pulsed vibro boiling layer was chosen, since it allows improving the quality of the finished product by lowering the temperature of the drying agent, thereby retaining a significant amount of nutrients in the original product. To study the kinetic and hydrodynamic dependences of the drying process, an experimental setup has been developed and created, which allows to obtain the most accurate and reproducible results. According to the results of the experiments done, the drying curves, the drying rate curves and the heating curves were constructed. The technological modes of operation of the drying unit are determined, ensuring a minimum of the specific energy consumption of the drying process and the maximum moisture stress of the drying chamber. In addition to the experiment on drying apple pomace, a study was also conducted on the content of pectic substances in dried pomace. To determine the amount of pectin and protopectin, the calcium-pectate method was used. During the experiment, it was found that with the proposed method of drying, the yield of pectin substances is increased compared with traditional methods. Histograms of the content of pectin and protopectin were constructed depending on the method of drying. A comparative analysis of the content of pectin and protopectin was carried out depending on the drying mode for apple pomace and sugar beet pulp. The conclusion is made about the increased thermolability of protopectin in apple pomace compared to sugar beet pulp.

drying, apple residue, beet press, kinetics, hydrodynamics, moisture tension, pectin, protopectin, thermolability

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