Determination of the antioxidant and antiradical activity in berry and fruit juices and wines

Antioxidants can be found in various plants, such as fruits and berries, and also in their derivative products i.e., juices and wine. There already is a number of studies on grape wines, however, the research on berry and fruit wines, which undergo processes that are similar to grape juice production and fermentation, is still lacking. Our interest was to determine the antioxidant and antiradical activity, as well as the concentration of polyphenols in the juices and the respective wines, and find out if remains at the original level after fermentation. Various berry and fruit juices, prepared for wine fermentation, as well as ready wine samples, were studied. To characterize the antioxidant and antiradical properties in juices and wines, the polyphenol content was determined using the Folin-Ciocalteu method, the antiradical capacity was measured using the DPPH method, and the antioxidant activity - using the FRAP method. The data obtained in the study were processed and analyzed using MS Excel program. Blackcurrant, redcurrant, apple, rhubarb, gooseberry homemade juices, and their respective wines were analyzed. The highest polyphenol concentration, antiradical capacity, and antioxidant activity were determined in the blackcurrant juice and wine, while the lowest numbers were observed in the rhubarb juice and wine. There was no significant reduction in the antiradical activity (DPPH) or antioxidant capacity (FRAP) in the wine fermentation process of the respective juices, besides the fact that the activity decreased proportionally to the dilution of the juices during the wine manufacturing. Not only various berry and fruit juices, but also wines provide valuable antioxidant and antiradical activity.