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Isolation and study of a bioactive extract enriched with anthocyanin from red grape pomace (Cabernet Sauvignon)
Grape pomace is a natural product rich in dietary fibers, polyphenols and anthocyanidins. By their chemical composition, secondary products from grape processing are valuable raw materials for obtaining a variety of new products. Recently, in food biotechnology, fermented and unfermented grape pomace have undergone a deeper study of the role of additives in dry powders or extracts. The quality and biological value of natural food products are determined by their chemical composition and a whole complex of integral organoleptic properties that depend on this composition. Natural anthocyanin dyes not only give color to vegetable raw materials, but also have a well-known physiological activity, in particular, coloring and antioxidant. Purified natural dyes have recently been increasingly used to improve the consumer properties of food products, in biologically active additives, in pharmaceutical preparations for the treatment and prevention of various diseases. At the same time, the composition of anthocyanins, even for the same variety of plant raw materials, is complex and variable; it depends on climatic conditions, on the maturity of berries, root crops, and the quality of agricultural work. Anthocyanins easily undergo a number of transformations depending on the conditions of extraction and analysis. The originality and novelty of the isolation and production of biologically active extracts with antiradical properties from by-products of local wineries in ecologically safe areas of southern Kazakhstan lies in the fact that natural environmental conditions: high temperatures and low humidity which contribute to the formation of biologically active substances with increased concentrations. Current research was aimed at the deep study of extracts from grape pomace rich - anthocyanins. Red grape pomaces of Vitis vinifera L. Cabernet Sauvignon were extracted using a solvent-based (SE) method with concentrations of 70% v/v and solid/liquid ratios of 1:10, followed by incubation at three different temperatures of 30 °C, 40 °C, and 50 °C for 1 h, 2 h, 3 h, and 4 h. All solvent extracts showed higher amounts of anthocyanin pigments. The maximum yield was obtained by using the optimal time of extraction (2 h at 50 °C), with the highest total anthocyanin recovery obtained by means of 70% ethanol. The anti-radical and toxic effects of the obtained extract (anthocyanin) were studied.