Fruit growing
and viticulture of South Russia

Annotation

The article presents the results of studying the quality indicators of wine alcohols, distillates and wine material from various grape raw materials to ground the possibility of developing a technology of high-quality wine spirits, including the processing of fresh grapes for wine materials without sulfitation and the use of enzyme preparations, and clarification of grape must by sedimentation, distillation of wine materials and rectification of the obtained distillates using the modes that allow to obtain wine alcohols with a strength of at least 94 % vol. It was found hat the yield of grape must of table grape varieties is low � 70.8 dal out of 1033 tons of grapes. In an dry wine material from table varieties, the mass concentration of volatile acids exceeded the maximum permissible limit � 1.60 g/dm3 . It is noted that during distillation of wine materials, the strength of distillate obtained is directly proportional to the volume fraction of ethyl alcohol of the original raw material and it was 31.9 % vol. (table grapes) and 39.5 % vol. (Crystal). Analysis of the volatile components of distillates and wine alcohols showed that the mass concentrations of the compounds analyzed in the wine alcohols are directly proportional to their content in the corresponding distillates; there is also a positive trend in reducing undesirable components in the rectificate produced. The selected rectification mode made it possible to reduce the amount of higher alcohols by 1.5 times for the Crystal variety and by 4.7 times for the table varieties. The content of esters in wine alcohols increased in 2-2.5 times mainly due to ethyl acetate, the boiling point of which is close to the boiling point of ethanol. It is shown that to obtain high-quality wine alcohols, it is advisable to use the substandard grapes both table varieties and technical varieties as raw materials.

Annotation

This article proposes a technology for the production of grape spirits from a sweet grape pomace, which consists in fermentation of the grape pomace using a pure growth of yeast, adding yeasty grounds and water, a piquette separation, its distillation with the selection of the head and tail fractions and the secondary distillation to obtain a 94-95 % grape rectified spirit by volume. The distillation of the resulting raw materials was performed on the installation of a LUMMARK consisting of a distiller and a distillation column. The prepared piquettes were subjected to primary distillation using the DV-3 distillator, distillates (raw spirit) were distilled on the RUM-3 distillation column with electrical heating. Primary distillation mode: the volume of the piquette taken to distillation is 50 l, the heating mode before the distillation starts at the power of the electric heater � 3kW (55-65 min). The rectifying distillation mode: the volume of the raw alcohol is 40 l, the heating mode before the selection of the head fraction is started with the power of the electric heater � 3kW (40-55 min). In the preparation of raw materials to primary distillation, it was established that the optimal duration of the fermentation of raw materials for the production of piquettes in order to reduce the content of volatile acids, methanol and other secondary fermentation products that have a negative effect on finished products should not exceed 4 days. It has been established that to obtain high-quality raw spirit, it is necessary to carry out the selection of head fractions in an amount of at least 3 % of the volume for all raw materials, for distillate from grape must of technical varieties of grapes � at least 1.5 % of the volume. It is shown that the organoleptic and physicochemical indicators of rectified grape spirits, produced by the proposed technology, corresponded to the standards established in the standard regardless of the type of raw materials (wine grape, table grape).

Annotation

A comparative analysis of wine and grape distillates and wine and grape alcohols obtained by rectification from bulk wine and yeast sediments from Kristall grape variety was carried out. The process of distillation of bulk wine and yeast sediments was conducted in two stages. The process of primary distillation with the production of crude alcohol was carried out in a distiller, and secondary distillation with the production of alcohols � in a small rectification unit with electric heating. Obtaining crude alcohol from yeast sediments was conducted using a steam generator as a source of live steam. It was found that during the distillation (primary distillation) of bulk wine and yeast sediments into crude alcohol, the volume fraction of ethyl alcohol in the raw alcohol depended on the volume fraction of ethyl alcohol in the initial distilled raw material. In distillates and grape alcohols from yeast sediments, the content of esters is significantly higher than in wine distillate and alcohol. Wine alcohol contains fewer volatile components compared to grape alcohol from yeast sediments. Rectification made it possible to significantly reduce the concentration of unwanted volatile components (fusel alcohols � isobutanol, isopentanol, and others). It was found that the content of esters and higher alcohols during distillation varies depending on the volume fraction of ethyl alcohol in the distillate. At a lower volume fraction of ethyl alcohol of wine or grape alcohol (less than 95% vol.), the content of undesirable higher alcohols in the rectified alcohol increases. A 2-fold increase in the content of methanol in the distillate and alcohol from yeast sediments was revealed, which requires additional research to optimize the technology for obtaining safe grape alcohol from yeast sediments.