Potencial antioxidante de kombucha de chás (Camellia sinensis) e ora-pro-nóbis (Pereskia aculeata Miller)

Abstract

The demand for foods that provide health benefits has been growing in the country. In this case, the increase in food products aimed at this market niche is remarkable. However, regarding potentially functional drinks with high protein content and plant based there are few options. Thus, the fermented tea drink (Camellia sinensis), called kombucha, is being incorporated into the diet of many Brazilians, this is mainly justified by the fact that it presents itself as a possible source of benefits to human health through the chemical compounds derived from its fermentation. In parallel, ora-pro-nobis is widely known for its high protein content and antioxidant potential, and can be used in different food formulations. In this project, green tea-based kombuchas were prepared with different flavors (white tea, green tea, black tea and ora-pro-nobis) in order to add antioxidant compounds to the drink, consequently enhancing the likely health benefits. Physical-chemical analyzes (pH, volatile acidity, titratable acidity, total soluble solids, alcohol content and proteins), potential antioxidants (DPPH, ABTS, FRAP) were performed, in addition to determinations of phenolic compounds (CFT) and total flavonoids (FT)) and sensory analysis (acceptance and preference test), in addition to statistical tests of principal component analysis (PSA) and VIP score. The results obtained in this study for the physical-chemical parameters were in accordance with the Brazilian legislation, requiring some adjustments in the F4, F2, F1 and F3 formulations to increase the volatile acidity content, which was close to the established minimum limit. All kombuchas had an alcohol content below 0.5%, being defined as non-alcoholic. The pH presented levels close to the minimum limit of the legislation, occurred due to the acidification of the initial preparation solution with the donation of Scobys and starter solution. The kombuchas made with ora-pro-nobis had at least twice as much protein than the formulations without ora-pro-nobis. The antioxidant potential of F1 showed higher levels in all analyzes performed (ABTS, DPPH, FRAP, CFT, FT), followed by F1 and F5, with the lowest levels evaluated being found in F2 and F4 (FRAP, CFT, FT). The kombuchas evaluated in the microbiological analyzes of Total Coliforms at 45 °C and Salmonella did not show growth, being considered safe for consumption. For the sensory analysis evaluating the global preference parameter, there was no significant difference by the Tukey test (p≤0.05) between the formulations. In the average Acceptability Index (AI) evaluated, all formulations obtained a percentage of acceptability above 66%, F3 (69.29%) obtained the highest index. In this sense, it can be concluded that the kombuchas with ora-pro-nobis (F4, F5, F6 and F7) showed protein potential, however low levels of antioxidant compounds. Kombucha F3 flavored with 100% black tea showed sensory and antioxidant potential. Kombucha F1 made with 100% green tea, showed high antioxidant potential.