The usage of secondary raw materials of the wine industry in biotechnology of fermentation beverages

It is proposed to use a liquid extract obtained from "sweet" grape pomace - waste of processing berries into wine materials, in the production technology of fermentation kvass. The objects of the study were: grapes of the ampelographic variety “Pinot Noir”; an extract obtained from dried "sweet" pomace of grapes remaining after the separation of the fermented juice; unfiltered unpasteurized unclarified kvass, obtained according to the classical technology on the concentrate of kvass wort with the addition of an extract from the pomace of grapes. The extract was obtained from grape pomace, pre-dried to a moisture content of 6% and ground to a particle size of 0.05 mm, by water extraction for 1.5 h at a temperature of 77–80 ° C at a hydromodule of 1: 14; the resulting liquid extract contains 2.0-2.2 g / 100 ml of polyphenolic substances. The extract was added to the composition of kvass "before fermentation" (at the stage of preparation of the main wort) and "after fermentation" (at the stage of blending the finished kvass). It was found that the introduction of the extract into the composition of kvass before the main fermentation promotes a better fermentation of dry substances, a higher content of polyphenols in the finished drink and a higher colloidal stability of these drinks. The samples with the addition of 10-15% extract were recognized as the best in terms of tasting qualities. According to the results of the study, the introduction of an extract from grape pomace into the composition of fermentation kvass is recommended at the stage of preparation of the main wort, in a dosage of 10% of the total mass of the main wort. 200-250 ml of kvass with such a dosage of grape pomace extract allows satisfying from 43% to 60% of the average daily requirement for polyphenolic substances.