Fruit growing
and viticulture of South Russia

Annotation

Organic acids and products of their transformations play a great role in formation of organoleptic qualities of sherry wine not only in terms of taste component, but also as a regulator of redox processes. Organic acids are mainly represented in wine by tartaric, malic, lactic, succinic, acetic, citric, oxalic acids and others. Each acid included in the wine, has its own taste properties, which in interaction can enhance or neutralize each other. The article presents data on changes in the content of organic acids during the production of sherry type wines by filmless method from white grape varieties Platovsky, Kristall, Aligote. On the basis of the conducted studies, it was revealed that during oxidative aging of sherry wine materials on yeast sediments, some quantitative changes in the composition of organic acids occurred. In all variants there was a decrease in tartaric acid concentration. Its greatest decrease (by 1.5 g/dm3 ) was observed in the control Aligote. The concentration of malic acid decreased by 16-92 % in the studied variants Platovsky V-1, V-2, Kristall V-1 and the control Aligote. The greatest decrease in malic acid in the process of aging on the yeast sludge observed in the control Aligote (92 %). Also, there was an increase in lactic acid by 1.7 g/dm3 . An increase in the concentration of succinic acid (by 25-30 %) and acetic acid by 0.11-0.41 g/dm3 was observed in all samples. It was noted that changes in the quantitative composition of organic acids in sherry type wines are predominantly influenced by the production method o f sherry type wines.

Annotation

Organic acids of grapes play a big role in the wine quality formation. Acid total content is one of the indicators of the grapes suitability for the wine preparation of particular type. The research was conducted on white technical grapes Tsvetochny, Donus, Platovskiy, Stanichny, Crystal, Bianca, Lakhed Mezesh, Aligote, grown in the vineyards Novocherkassk Department of AllRSTIV&W Experienced field. The paper presents data on the composition of organic acids in the studied worts and wines and about their changes in the process of preparation and formation of wine. The results of studies carried out revealed that in the wort of all studied varieties was observed the predominance of tartaric acid above malic acid by several times, with the highest its content in the Lakhed Mezesh and Tsvetochny varieties. The highest concentration of malic acid was observed in the wort from the Bianca grape variety. In the wort from the grape varieties of Donus, Crystal, Bianca, the presence of a small amount of succinic acid was noted. The highest value of the total share of tartaric and malic acids (from all wine acids) was observed in the experimental sample of wine from the Lakhed Mezesh variety, and the lowest one is in the sample from the Stanichny variety. The highest content of succinic acid was observed in the wines from the Crystal and Bianca grape varieties. The highest ratings (8.7 points each) were given to the wines from the Aligote, the Stanichny and the Lakhed Mezesh grape varieties. It is noted that the composition of organic acids in the grapes and the wine largely depends on the varietal characteristics of the grapes as well as the zone of its growing.

Annotation

Amino acids are the most important group of organic nitrogenous substances in grapes. In the initial period of grape ripening there are few amino acids in grapes. During ripening their qualitative and quantitative composition noticeably changes. The amount of amino acids in grapes depends on variety, climatic conditions, soil composition, ripeness at harvest, method of processing, particularly the duration of contact of must with the hard parts of the bunch and many other factors. At the beginning of alcoholic fermentation there is an active consumption of amino acids by the yeast, and afterwards, as it dies off, the yeast enriches the wine with them. These compounds influence the formation of aroma and flavor of wines, as they are the precursors of many aromatic compounds. The purpose of the study is to establish the features of the biochemical composition of amino acids in liqueur wines of the port type prepared from white hybrid grape varieties. The objects of the study were liqueur wines of port type from white technical grape varieties of interspecific origin: Kristall, Platovskiy and Stanichnyi. Wine material prepared from Aligote variety was taken as a control. On the basis of the conducted studies, it was found that the total sum of amino acids in the experimental sample prepared from the Platovskiy grape variety was significantly higher compared to the other experimental wines (2692 mg/dm3 ). Proline dominates among the amino acids of all the test samples by mass concentration, its percentage of the total sum of amino acids in the studied wines was: Aligote (control) � 86,3 %; Kristall � 81 %; Stanichnyi � 51,4 %; Platovskiy � 83 %. The highest levels of amino acids arginine (162.5 mg/dm3 ), and leucine (4.88 mg/dm3 ) were observed in the wine made from Stanichnyi. The experimental variant of the variety Platovskiy had a fairly high content of ß-phenylalanine (23.67 mg/dm3 ) compared with other, and the highest amount of valuable amino acids: tyrosine � 63.07 mg/dm3 ; serine � 24.01 mg/dm3 ; threonine � 138.6 mg/dm3 ; ɑ-alanine � 26.61 mg/dm3 . The highest glycine content was observed in the wines prepared from the varieties Kristall (7.24 mg/dm3) and Platovskiy (7.89 mg/dm3).

Annotation

The varietal characteristics of the grapes are of great importance when choosing the direction of their use. These features include the color of the grape and its flavor characteristics, the presence of coloring agents in the berry, the ripening period, etc. Features of the variety are reflected in the quality of the wine and its organoleptic properties. The physical and chemical composition of the must and wine varies greatly depending on the quality of the grape and its variety, the natural conditions of the cultivation area, agricultural technology and technology of wine preparation. So, different grape varieties have different amounts of sugar, organic acids, minerals, enzymes and vitamins in the berries. This paper presents the results of a comparative analysis of must and wines prepared from white grape varieties of interspecific origin, grown under the same conditions. The objects of research were must and wines from white technical grape varieties of the ARSRFVW breeding � Tsvetochny, Donus, Platovsky, Stanichny, Hungarian varieties � Crystal, Bianka, Lakhed mezesh and the Western European Aligote grape variety grown in the vineyards of the Novocherkassk department of the Experimental Field located at the SRFVW. The research was carried out on the basis of the wine-making technology laboratory and the quality control of grape and wine products laboratory of SRFVW. Experienced wines were prepared under micro-winemaking conditions according to the classical technology for dry white wines using the technological equipment for grape processing. The organoleptic analysis of the wines under the study showed that the experimental samples of wines from grape varieties of Aligote, Lakhed Mezesh and Stanichny had the brightest varietal aroma and full harmonious taste and received a high tasting score (8.7 points). It has been established that the chemical composition and organoleptic properties of wines made from grape varieties of interspecific origin largely depend on the varietal characteristics of the grapes.

Annotation

Among a number of natural factors that ensure the development of the grapevine and predetermine the quality of wine, the soil belongs to one of the first places, since the soil for the grape plant is an important part of the habitat. The type of soil on which the vineyard grows, as well as its soil-forming rock, enriched with primary minerals and a large number of trace elements, are important. The soil contributes such substances to the plant, which have a particular impact on the quality and individual characteristics of the products obtained from grapes. The soil determines the fullness, finesse and bouquet, and often the type of wine itself. The winemaker only assists in the smooth flow of the process and the identification of those qualities which are already present in the must. The research objects were the must and the wines from the grape variety Flower, grown on the following types of soils: carbonate chernozems (B-1), sandy soils (B-2), chestnut soils (B-3). The research was carried out on the basis of the laboratory of quality control of grape and wine products and of ARRIV&W, a branch of FSBSI FRASC. The research revealed the influence of different types of soils on the physico-chemical parameters of musts and wines, in particular on the content of titratable acids, as well as phenolic and nitrogenous substances, which play an important role in the formation of organoleptic properties of wines. According to the organoleptic analysis, the highest tasting score (8.7 points) was given to a wine sample made from grapes grown on chestnut soils, which had the most complete and harmonious taste with light nutmeg and floral tones in the aroma.