INFLUENCE OF DRY CONCENTRATION OF DRY SUBSTANCES ON FEATURES OF OSMOPHILIC ALCOHOLIC RACES OF YEAST

• Main Authors: S. Kovalchuk, T. Mudrak
• Format: Article
• Language: English
• Published: Odessa National Academy of Food Technologies 2021-03-01
• Series: Harčova Nauka ì Tehnologìâ
• Subjects: spirit yeasts; cultivation; highly concentrated wort; dry matter
• Online Access: https://journals.onaft.edu.ua/index.php/foodtech/article/view/1967
• ISSN: 2073-8684; 2409-7004

The main factors influencing the cultivation environment on the growth and development of different races of alcoholic yeast have been studied. The following races were selected for studies of the influence of wort dry matter concentration on morpho-physiological features of alcoholic yeast yeast cells: S. cerevisiae ДО–16, ДО–11, K-81, XII. The novelty of the work lies in the study of the influence of the concentration of dry matter of the wort on the morpho-physiological features of alcoholic yeast, screening of alcoholic races for fermentation of highly concentrated wort. The morphology of cells of alcoholic races of the yeast S. cerevisiae, which are cultured on starch-containing medium, has been insufficiently studied. It was found that the cells of the alcoholic yeast race S. cerevisiaeДО-16 and ДО-11 had smaller cell sizes in comparison with the thermotolerant and mesophilic races S. cerevisiae K-81 and XII at a concentration of DM wort of 28%. However, the number of yeast cells in S. cerevisiae ДО-16 and ДО-11 races is higher. During the fermentation of highly concentrated wort, these indicators characterize the increase in the working surface of the yeast in the fermented medium, which allows to intensify the fermentation process. Studies have been conducted on the effect of dry matter concentration on the size and shape of giant colonies of alcoholic races of yeast. Culture samples were taken in the stationary phase of growth. Studies of giant colonies of alcoholic breeds of yeast cultured on wort at a concentration of 28% DM indicate that the race of S. cerevisiae ДО-16, in comparison with other races, is able to withstand high concentrations of wort. After all, the size and shape of the giant colonies of this race indicate that the yeast cells were in a satisfactory physiological condition. According to morpho-physiological characteristics, alcoholic yeast of race S. cerevisiae ДО–16, ДО–11, K–81, XII with thermotolerant and osmophilic properties for fermentation of highly concentrated wort was screened Based on theoretical and experimental studies, it was found that the selected race of yeast S. cerevisiae ДО-16 on morpho-physiological characteristics has advantages over races ДО-11, K-81, XII for fermentation of high concentrations of wort. Thus, for fermentation of highly concentrated wort from grain raw materials, a highly productive race of alcoholic yeast with increased osmophilicity - S. cerevisiae ДО –16 was selected.