Avaliação do potencial de resíduo de vinícola visando o desenvolvimento de bebida fermentada a partir do consórcio de kombucha

Abstract

The improvement in the quality of life drives the search for products that play roles in the prevention and treatment of diseases, such as the so-called functional foods. The fermented tea called kombucha is reported in the literature with functional characteristics, as its composition contains bioactive compounds such as polyphenols and organic acids. The basis of fermentation of kombucha is the source of sucrose and tea from the varieties of the Camellia sinensis plant, however the use of alternative sources of substrates for the preparation of tea has been considered in some scientific works. It is known that during the process of industrialization of the grape, residues are generated, which are normally destined for composting. Considering that these residues are rich in nutrients such as extractives, nitrogen and bioactive compounds, the present work aimed to evaluate these residues in obtaining kombucha. In order to evaluate the bioavailability of these compounds, a previous study was necessary in order to evaluate the extraction conditions of the residues in natura format and flour of the material obtained after its crushing and milling. According to the results, it was defined that the best applicability of the use of residues referred to the flour condition compared to the in natura residue, since the rates of phenolic compounds were higher in the first condition (628.39 mg EAG/L), which is desirable from the point of view of the presence of antioxidants in the drink. Subsequently, fermentations were carried out with different proportions of flour from the residues (0.5%, 3%, 6% and 9% m/v), as well as a control experiment with green tea (0.5% m/v). The results showed maximum levels of phenolic compounds in the fermentation of grape residue flour in the 9% condition (m/v), reaching 1157.80 mg EAG/L and antioxidant activity of 2817.5 µmol TE/L in the condition at 6% (w/v), at the end of fermentation. In this way, the present work showed the potential use of winery by-products as a potential source of bioactive compounds in the preparation of kombucha and at the same time provided an improvement in industrial practices so that its reuse helps in ecological management.