Effect of Pure Culture of Yeast on the Characteristics of Wine Quality

Abstract

Saperavi is one of the most distinguished varieties of wine among the grape varieties widely spread in Georgia. Along with the grapevine variety, the pure culture of yeast also plays a crucial role in producing high quality wine material, because wine is the product of the viability of yeast. All chemical transformations that take place during the alcoholic fermentation, as a result of which the grape juice is turned into a qualitatively new product, i.e. wine, are carried out by direct involvement of the ferment system of the yeast. In addition, in the process of viability, the yeast produces not only the primary products of fermentation (ethanol and carbon dioxide), but also a number of organic substances (secondary and by -products) that play a big role in forming the wine taste and aroma, as well as the antioxidants, which provide its sustainability, and some biologically active components. Therefore, selecting the pure culture of wine yeast and directing the alcoholic fermentation correctly with the use of it, will guarantee to obtain a high quality product.