Phenolic Composition, Chromatic Parameters and Antioxidant Activity “in vitro” in Tropical Brazilian Red Wines

Red wines are a rich source of several classes of polyphenols that have the ability to act as antioxidants chelating metals, inhibiting lipid peroxidation and sequestering free radicals scavenging. Our study aims to determine the phenolic composition, chromatic parameters and antioxidant activity “in vitro” in tropical Brazilian red wines from the Syrah and Cabernet Sauvignon varieties of the 2011, 2013 and 2014 vintages from Sao Francisco Valley. Total polyphenols, polyphenols index, total anthocyanins, condensed tannins, color intensity, tonality and the phenolic profile was determined. Consequently, color index ranged from 8.08 to 15.03; tonality between 0.72 and 1.0; total phenolics expressed as gallic acid equivalents ranged between 1,528.90 mg.L-1 and 4,003.96 mg.L-1; anthocyanins ranged between 98.94 mg.L-1 and 501.2 mg.L-1 amd condensed tannins between 61.08 and 147.74 mg.L-1. Resveratrol presented means ranging between 2.75 and 26.89 mg.L-1, and the antioxidant activity ranged from 58.02% to 95.70%. We did not observe correlation between anthocyanins and color with antioxidant capacity. The results of this study showed better values of polyphenols and potent antioxidant activity when compared with other studies. These results can be associated with possible beneficial effects on health.