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By using the classical technology of making dry white wines, which does not involve maceration of the pomace, we can produce standard table wines, light and delicate. This minimises such an objectionable factor as saturation of the wine with extra nitrogenous and phenolic substances and oxidative enzymes. On the other hand, this scheme gives a specific varietal aroma no chance to reveal itself more expressively. The paper overviews briefly the scientific works considering the modes of pomace maceration before fermentation and the use of enzyme preparations in the technology of white table wines. The physicochemical and sensory characteristics of wine materials from Rkatsiteli grapes grown in the south of the Mykolaiv Region have been analysed. This analysis has proved that standard white table wine materials can be obtained both by the traditional method (the so called ‘white’ method) and with the use of short-term maceration of the pomace. Macerating the pomace resulted in obtaining fuller, richer wine materials with a bright aroma and good body. It has been shown that to obtain bright and not too blunt wine materials, the most essential parameter of the maceration process is its low temperature. A pectolytic enzyme preparation used during maceration increased, to some extent, the mass concentration of phenolic substances, the reduced extract, the optical density, and the concentration of terpene alcohols. Besides, it allowed fuller revealing a wine’s aromatic profile. The research has resulted in establishing that there is regularity in how the concentration of terpene alcohols changes with different temperature conditions of steeping the pomace. It has been shown that the maximum concentration of terpenes responsible for the varietal aroma is best retained in wine materials when the maceration temperature is 5°C. A rise in the pomace maceration temperature to 20°C led to a decrease in the concentration of labile terpene alcohols, so it should be avoided in producing quality wines. Studying different maceration modes has allowed recommending a certain method to manufacture full-bodied, well-structured white table wines with a pronounced varietal aroma. This method involves adding the enzyme preparation Depectil CLARIFICATION to the pomace and macerating it for 12 hours at 5°C. [ABSTRACT FROM AUTHOR]

One of the most important problems of the modern wine technology is the production of high quality and competitive products. It is commonly known that the quality of a wine largely depends on the yeast race. The main requirement for yeast is completeness of fermentation, which depends on the amount of yeast involved, aeration, initial content of various substances in the must, temperature, pH of the environment. Using imported materials in the specific conditions of national winemaking requires laboratory and industrial research to rationalize the use of local and foreign pure yeast cultures and to accelerate the process of grape must fermentation. So, this study considers how the yeast origin and additional nutrition effect on grape must fermentation and influence the physicochemical and organoleptic characteristics of wine materials obtained from the white grape varieties Aromatny and Zagrei of the generative breeding by the National Scientific Centre Tairov Viticulture and Winemaking Institute. Besides, it has been concluded whether using additional nutrition is practical. It has been established that the fermentation process was complete in both the control and the experimental samples. There were no facts of underfermentation. When supplementary nitrogenous nutrition was used, the fermentation activity of yeast increased and the fermentation process ended faster. The dynamics of the total number of cells of the Aromatic and Zagrei varieties was the same during the years 2015-2017 and did not depend on the fermentation scheme. It has been found that the fermentation process does not depend on supplementary nutrition, but the yeast race effects on the physicochemical parameters, namely on the volatile acids content. The results obtained have shown the effect of a yeast race and supplementary nutrition on the organoleptic characteristics of these varieties. In Southern Ukraine, to control the quality characteristics of wine materials, using active dry yeast Saccharomyces cerevisiae with a two-stage nutrition complex has a positive effect on the physicochemical parameters of the corresponding grape variety and allows revealing its varietal characteristics. [ABSTRACT FROM AUTHOR]