Testing some production technologies of red grape juice in the Republic of Moldova

Abstract

The process of primary processing of black grapes in viticulture and canning branches aims to mechanize the process of extracting the colour from the whole grapes before the fermentation of the must in order to obtain different types of red juice and red wine. To be solved: simplification of the scheme and the creation of the universal technological line for juice - wine with increased hygienic properties and reduced expenses. The whole grapes received in the bunker-press are treated with 0.2% SO2 solution, hot 550C for 15 minutes, which can be recovered for other batches of raw material. The decontaminated grapes are thermally treated (selectively the skin) for 10-20 minutes with hot must +60-850C, followed by the first cycle of hydraulic (pneumatic) pressing with the separation of the pigmented dietary red must and storage. The rest of the mass in the bunker-press is dosed with potassium pyrosulfite together, dihydroxyfumaric acid and with hot must +600C for 10 minutes for the final extraction: anthocyanin - SBA, cooling it to +250C, pressing the second with the selection of the must fraction and fermentation to make red wine.