Improvement of White Fortified Wine Technology
Students Name: Hrytsiv Yurii Marianovych
Qualification Level: magister
Speciality: Fermentation Products and Wine-making Technologies
Institute: Institute of Chemistry and Chemical Technologies
Mode of Study: full
Academic Year: 2023-2024 н.р.
Language of Defence: ukrainian
Abstract: The object of research is the production of grape wines. The subject of the study is technological processes of production of fixed he. The purpose of the research is to improve the production of strong white wine, which provides a technical and economic effect and consists in increasing the yield of wine and reducing the duration of the process. Fortified wines are one of the most common fortified wines produced by the domestic wine industry. In the technology of strong, it is characterized by the addition of ethyl alcohol to the mash or wort during the fermentation of sugars, in order to stop the fermentation process and ensure a greater number of wine conditions. The actual moment of alcoholization (the time of introduction of ethyl alcohol) ensures the wine’s condition for sweetness and strength. At the same time, in accordance with current regulations, at the time of alcoholization, the substrate should contain at least 3% vol. naturally fermented alcohol. While providing strong whites, long-term contact of the wort with solid elements of the pulp is ensured to ensure the appropriate fullness and extractivity of the future wine [1]. The main factors under the influence of which the characteristic typical properties of strong wine are formed are the concentration of phenolic and other extractive substances, high temperature and oxygen. The formation of the color, taste, 8 and aroma of wine is mainly related to the transformation of phenolic compounds. The main component of the tannin complex of grapes is the catechin group, which includes d-catechin, l-gallocatechin, d-catechin gallate and their transformation products. The content of phenolic substances depends on the variety of grapes and the justified climatic conditions of its cultivation. Varieties differ in their ability to accumulate phenolic and extractive substances, in which the composition between the insufficient and solid phases is the smallest [2]. The Rkatsiteli grape variety, which was chosen as a raw material in this work, meets these requirements. In order to enrich the wine material with phenolic substances, the must is fermented on the mash. Another alternative way to ensure high extractability of the wine material is heat treatment and infusion of the wort on the must. The main task in wine production is the maximum extraction and transformation of aromatic, mainly phenolic substances from grapes into must and further into wine material in order to achieve the appropriate taste and aroma of wine [3, 4]. Enzymes play a key role in these processes. Although grapes are naturally rich in natural enzymes, the source of which are bacteria, yeast and fungi found on the surface of the bunches. However, many natural enzymes are inhibited, so it is advisable to add enzyme preparations of appropriate action at a certain technological stage of wine preparation. Oenological enzymes are a group of enzymes that are used for extraction, enhancing aromas and blocking lactic acid fermentation. Pectinases, hemicellulases and cellulases lyse the cells of grape berries and contribute to the extraction of aromatic precursors and polyphenolic compounds. To intensify the extraction of phenolic, nitrogen-containing aromatic substances, it is proposed to use enzyme preparations of pectolytic and cellulolytic action Vinozym FCE G and Tseloviridine Gx20, which allows to increase the yield of wort to 4%, reduce the duration of the stage of clarification, pressing and removal from sediments [5]. The formation of the taste and aroma of strong wine is also influenced by the heat treatment of the wine material. Classically, wines are aged in oak barrels in the 9 presence of oxygen at a temperature of up to 30 °C and a humidity of 70 to 75% on sunny sites for a long time. Therefore, it is proposed to improve the production of strong white wine, which provides a technical and economic effect, and which consists in increasing the yield of wine and reducing the duration of the process due to: 1. Use of Uvazym extra (Enogrup) enzyme drug of pectolytic action with additional cellulose and hemicellulase activity at the stage of heat treatment of the pulp. This drug is advisable to use when infusing white grape pulp. Helps to reduce the viscosity of the wort, facilitates and accelerates the separation and clarification of the wort, increases the yield of the wort by 6...8%. 2. Use of the scheme of continuous fermentation of wort, which has the following advantages in comparison with the periodic method: • There is no wort fermentation period. The productivity of the fermentation plant increases and the yield of wine per unit volume of the fermentation tank increases. • Fresh wort is fed into the fermenting wort, which has at least 4% vol. alcohol Therefore, fermentation takes place with the participation of wine yeast (Saccharomyces vini), which is more alcohol-resistant than foreign yeast (Apiculatus and others) arriving with fresh must. This contributes to obtaining high-quality, healthy wines with a clean aroma and taste. • The fermentation process can be fully mechanized and automated, which ensures the uniformity of the obtained wine. 3. The use of a special heat treatment unit for wine to give it its typicality, which ensures continuous pumping of wine with its simultaneous air aeration, which intensifies the process of wine maturation and shortens its duration. Taking into account the above improvements, a technology for the production of strong white wine from grapes of the Rkatsiteli variety with a productivity of 10 t/h has been developed. Key words - white strong wine, technology, fermentation, grapes, enzyme preparation.