Improvement of the blending technology of medium dry and semi-sweet white table wines

The paper reviews the literature on the existing technologies of medium dry and semi-sweet table wines. The main problems of manufacturing this type of wines have been outlined, as well as how they are solved by domestic and foreign winemakers. The classical scheme of producing medium dry and semi-sweet wines allows retaining the aroma of a certain grape variety and obtaining quality wines, but it is not applied in Ukraine as it is technologically complicated and costly. The scheme that involves blending is far more economical, but does not allow retaining all the fine aromatic nuances of a variety. So, the article considers the ways of obtaining medium dry and semi-sweet wines using grape must that has been concentrated by freezing. It has been shown that this technology will allow retaining the valuable substances of the variety aroma and will be the basis for producing the highest-quality wines of this type. For the research, the following samples have been analysed: clarified must of the Rkatsiteli and Citronny Magaracha grape varieties, must concentrated by freezing, vacuum must, dry wine materials, and the medium dry white table wines made from them. In the musts and wines, the main physical and chemical characteristics have been studied (the mass concentrations of sugar, titrated acids, total and free sulphur dioxide), as well as some additional parameters (the pH, mass concentrations of phenolic substances, free and bound terpene alcohols, optical density with the wavelength 420 nm). The mass concentrations of volatile acids and the sensory characteristics of the wine materials and wines have been determined, too. The research has shown that in the medium dry wines obtained by cryotechnology, the concentrations of free terpene compounds increased from 1.01 mg/dm3 to 1.21 mg/dm3 in Rkatsiteli, and from 2.89 mg/dm3 to 3.24 mg/dm3 in Citronny Magaracha. The flavour and aroma improved substantially, too. So, the blending technology of producing medium dry and semi-sweet table wines using cryomust allows retaining, to the greatest possible degree, the bright and peculiar aroma of the grape variety, and obtaining the highest-quality wines of this type.