Study of physic-chemical and biochemical parameters of technical varieties of grapes

Abstract

The authors studied introduced (Aligote, Rkatsiteli, White Muscat, Riesling Rhine), indigenous (Kokur white, Sabbat) and classified varieties of grapes of Magarach Institute (first-born Magarach, Citron Magaracha, Muscat aligote), growing in Crimea, according to physicochemical and biochemical indicators. The feature of grape aromatic varieties is the high content of phenolic substances in the must (404–640 mg/l), the activity of monophenol-monooxygenase, macerating ability. Indigenous grape varieties are characterized by a low content of titratable acids. The activity of monophenol-monooxygenase is interconnected with the content of phenolic substances in the must (r = 0.77). The ratio of tartaric and malic acids increases in the series introduced → indigenous → classified varieties. The values of the glucose-fructose index in the samples are 0.84–1.00. The obtained patterns make it possible to regulate the course of redox processes; to optimize the regimes and parameters of grape processing in the production of different types of wines.