Fruit growing
and viticulture of South Russia

Annotation

The relevance of the work lies in the necessity of replacing animal proteins (gelatin and its analogs, fish glue) with vegetable proteins in the processing of wine materials in order to clarify and stabilize them. The influence of potato protein on clarification and physical and chemical parameters of white, rose and red table and liqueur wine materials was investigated. The optimal technological dosages of potato protein were established using trial fining in comparison with the generally accepted gelatin treatment. It was shown that the optimal technological dosages of potato protein, which provided the desired transparency of wine materials, were 2-4 times higher in comparison with gelatin. Dosages of bentonite for complex technological processing were almost identical for gelatin and potato protein. The dynamics of clarification of wine materials was different: when gelatin was added, opalescence was formed in the processed wine materials, followed by aggregation and sedimentation of the sludge. The rapid formation of large aggregates and their settling were noted in case of application of potato protein in wine materials. The volume and weight of sludges in case of using potato protein were 10-15% more in comparison with gelatin. However, the sludges formed during the processing of wine materials with potato protein were denser and less mobile. With an increase in the dosage of potato protein, the turbidity and color intensity of wine materials decline, the mass concentration of phenolic compounds, the sum of colloids and the reduced extract decrease. The volume fraction of ethyl alcohol, mass concentrations of titratable and volatile acids, organoleptic indicators do not undergo significant changes. Based on the studies carried out, the application of potato protein for the processing of wines is recommended.

Annotation

The mass concentration of biogenic amines is an important indicator of the quality and safety of food products, including alcohol products. Biogenic amines are formed as a result of the decarboxylation of free amino acids by enzyme systems of microorganisms. It means that their formation has a biotechnological nature and is directly related to the vital activity of microorganisms. Contact of wine materials with microorganisms � yeast and malolactic bacteria, can lead to an increase in the concentration of amino acids and provoke the formation of biogenic amines. In this regard, the purpose of this research was to study changes in the concentrations of biogenic amines and amino acids in the process of alcohol and malolactic fermentation. Conducted studies have shown that the total concentration of biogenic amines in the grape must of both white and red grape varieties was minimal. Biogenic amines � methylamine and putrescine were not detected. It was found that as a result of alcohol and malolactic fermentation, the concentration of biogenic amines increased and the corresponding amino acids decreased. At the same time, the total concentration of all the studied amino acids in wine materials after alcohol fermentation increased, and after malolactic � slightly decreased, because part of the yeast cells was autolyzed during secondary fermentation of the wine materials. At the same time, mass exchange processes between the cell and the medium were activated, leading to enrichment of the wine material with amino acids. Thus, favorable conditions were created for the activation of decarboxylases, as a result of which there was an increase in the concentration of biogenic amines. The obtained data allow to suggest that in order to reduce the level of biogenic amines in the finished product, special attention must be paid to the selection of a race of yeast and malolactic bacteria that are unable to produce biogenic amines or introduce them in minimal amounts.

Annotation

This article presents the results of the study and systematization of the main ash elements and acid composition of varietal dry white wines made from grapes grown in the conditions of the Anapa-Taman and Central zones of the Krasnodar region. The relevance of the research is due to the lack of large data sets of indicators of authentic wine products to establish significant correlations and develop automated models for assessing the quality and authentication of wines, including with regional and varietal identification. As objects of research, varietal dry wines produced from white grape varieties grown in the conditions of the �Kuban� zone were selected: Aligote, Bianca, Viorica, white Muscat, Pervenets Magaracha, Pinot Blanc, Riesling Rhenish, Siber�kovyi, Sauvignon Blanc, Traminer, Tsitronnyi Magaracha, Chardonnay, etc. The wines were made using the same technology of low-oxidized pure white wines (100 % from one grape variety, hand-picking). Wine studies have been conducted annually since the 2013 harvest. The data were grouped as follows: mass and molar concentrations of equivalents of titrated acidity of wines, in terms of tartaric acid; total acidity, basic organic acids: tartaric, malic, succinic, citric, acetic, lactic; cations of alkaline and alkaline earth metals: potassium, sodium, magnesium, calcium; mass concentrations of ash and its alkalinity by varieties, grape harvest years and zones. It is shown that the minimum mass concentration of ash in genuine dry white wines produced in the Kuban zone is 0.86 g/dm3 , the minimum alkalinity of ash is 15.1 mmol-eqNaOH/dm3 . The results of the research will accelerate the rapid search and analysis of information for the development of a system of identification, quality control and establishing the authenticity of wine products with regional affiliation.