Study of the Alcohol Quality Obtained by Fermentation of Highly Concentrated Grain Wine by Different Races of Yeast
Authors: Kovalchuk Svitlana , Mudrak Tetyanа , Nakonechna Alina 
Published: June 2021

The topicality. Requirements for the quality of ethyl alcohol produced for further use in the production of alcoholic beverages are constantly increasing. This is due to the growing competition of producers of alcoholic beverages (improving the range and quality of products) and the revision of standards for products. New directions in the alcohol technology development require increasing the dry matter concentrations of the wort; fermentation at elevated temperatures and concentrations of alcohol in the brew; ensuring the reduction of the cost of alcohol by saving raw materials and energy resources. In such conditions, highly productive breeds of yeast with increased osmophilicity, thermotolerance and fermentation activity are required. Research related to the search for new strains producers of ethyl alcohol, and the technology development for highly concentrated mash from grain raw materials are relevant issues for the alcohol industry.
Purpose and methods. Investigation of the alcoholic yeast races influence on the synthesis of metabolites during fermentation of highly concentrated wort from grain raw materials. For research methods common to the alcohol and alcoholic beverages have been used.
Results. The influence of races of alcoholic yeast on the quality indicators of alcohol has been studied. It was found that the selected race of yeast S. cerevisiae DO-16 in the process of life synthesizes significantly fewer side metabolites compared to other studied races DO-11, K-81 and XII. The use of the selected race of S. cerevisiae DO-16 makes it possible to ferment highly concentrated wort from grain raw materials. It has been experimentally proved that at a concentration of DM concentration of the wort 28 %, the selected osmophilic strain of the yeast S. cerevisiae DO-16 provides regulated indicators of the hydrocarbon composition of mature brews and synthesizes up to 14.40 % vol. alcohol, respectively. To improve the qualitative sensory characteristics of ethanol, the possibility of metabolically adjusting the synthesis of volatile alcohol impurities using different races of alcoholic yeast was investigated.
Conclusions and discussions. Scientific novelty lies in the selection race for the yeast fermentation of corn mash highly concentrated with reduced alcohol content related impurities. The influence of yeast race on the formation of alcohol metabolites has been studied. The practical significance of the obtained results lies in the industrial implementation of the selected race of alcoholic yeast for fermentation of highly concentrated wort from grain raw materials. Prospects for further research are the possibility of influencing the quality of alcohol as a raw material for high-quality alcoholic beverages. During the fermentation of wort from grain raw materials, the qualitative and quantitative composition of volatile impurities of alcohol largely depends on the race of alcoholic yeast. The results of research on the biosynthesis of volatile impurities of alcohol allow you to adjust the quality of alcohol for the production of high quality alcoholic beverages.