Fruit growing
and viticulture of South Russia

Annotation

Of particular importance in wine-making is the problem of raw materials condition. In the wine-making regions of Russia we can observe a lower content of organic acids in the grape berries during fermentation and the lower of grape must acidity. The described phenomenon arises from the settling out wine acid salts during fermentation, in addition, harvesting is often carried out with insufficient sugar content and high acidity of berries. The most promising methods of influence the acidity are biological methods, as in the final product the side chemical substances are not formed. The work purpose is the development of new methods to improve the formation of aromatic substances and to increase in acidity of white wines biological methods. The paper discusses the impact of the 4 yeast strains in the acidity of the wine. The influence of the pH of the grape juice the accumulation of malic acid and glycerin is studied. The main focus was on malic acid, because it has been proven that the taste of the wine depends on its content. The initial content of malic acid in the samples was 0.67 g/dm3; 1.42 g/dm3 and 0.5 g/dm3. In the final product, its content increased in all of the samples. The best result was achieved with the use of France Elegance yeast: the amount of the accumulated malic acid increased in 2, 2.5 and 4 times respectively. The research results showed that the France Elegance yeast are the most promising for acidity control in white wines, regardless of the pH value, since only these yeasts accumulate a significant amount of malic acid.