Fruit growing
and viticulture of South Russia

Annotation

One of the most common ways to counterfeit the red wines is to adjust the coloring of cheaper white wine materials with both synthetic food colors (indigocarmine, carmoazine, etc.) and natural colors (extracts of blueberries, currants, etc.). The color characteristics of juice and wine products vary considerably depending on the type of feedstock, the technology of production, and the composition of the blend. In this regard, some unscrupulous manufacturers often use cheaper fruit and berry raw materials for coloring of grape wines. The purpose of the present research was the comparative characteristics of the phenolic complex and the optical characteristics of genuine red wines and falsifiers obtained using natural and synthetic dyes. The objects of research were table wine materials from Cabernet-Sauvignon and Rkatsiteli grapes, juices and fruit extracts, a mixture of synthetic dyes. The impact of natural and synthetic colourants on the optical characteristics of wine-making materials has been studied. Variation ranges were obtained for physical-chemical and optical parameters of model test solutions in terms of their colour intensity variation. The relation between colour intensity and phenolic compounds content along with monomeric anthocyanins was established (r=0.96 and 0.94, respectively). It was demonstrated that monomeric anthocyanins were absent in the model systems that contained synthetic adulterated winemaking materials. It is the significant difference in the qualitative composition of native and adaltirative wine materials: the total phenolic compounds and colour intensity index colourants were much lower in the coloured samples as compared to the established and recommended values for authentic wines, that allow to use these indicators in a set of criteria for identifying adulteration of wine products.

Annotation

Organic grape acids play a key role in sensory perception of wine and have a direct impact the formation of its organoleptic characteristics; contribute to the protection of wine materials and wines from the development of harmful bacterial microflora; affect the intensity of redox processes by inhibiting the action of oxidative enzymes; ensure the stability of wine products. The main grape berries acids (more than 90% of the total amount of acids) are tartaric and malic acids. Their content in grapes is due to a number of factors - grape variety, meteorological conditions during ripening, air temperature (cool conditions contribute to a higher content of malic acid in the ripe berries), water circulation in the plant stem, soil-microclimate complex, and agrotechnics of grape bush cultivation. The amount of these acids and their ratio largely determine the amount of titrated and active acidity of grapes. The purpose of this research was to study the composition of organic acids of grapes of European and Crimean aboriginal varieties from different soil and climatic regions of the Crimea. According to the results of research we have carried out the role of the grape variety in organic acid accumulation in the berries was confirmed. The similarity of grapes organic acids profiles was revealed between Pinot Blanc and Sary Pandas; Kokur Belyi, Rkatziteli and Muscat Belyi. The role of the soil and climatic conditions of grapes growing in the process of formation of composition of organic acids complex was shown. The possibility of using the organic acids complex as an indicator of the quality of grape raw material for the production of wines with geographic status as well as for optimization of technological methods of their production was confirmed.