The effect of polyphenolic composition as related to antioxidant capacity in white wines

Twenty-six white wines of "Appellation of Origin of High Quality", covering all viticultural areas of Greece were assayed for their polyphenolic content, using high-performance liquid chromatography coupled with diode array detector. Further, the anti-radical activity and reducing power of the wines were evaluated. In both cases, the antioxidant potency of the wines was correlated with the total polyphenol concentration, as well as with the concentration of the two major classes of white wine polyphenols, hydroxycinnamates and flavanols. It was found that wines contain in average 324.7 mg 1(-1) total hydroxycinnamates. (THC) and 52.2 mgl(-1) total non-hydroxycinnamates (TNHC), (catechin, epicatechin, gallic acid). The antiradical activity was correlated principally with total phenols (THC + TNHC) and with THC, but poorly with TNHC. By contrast, TNHC were found to exert sound reducing effect, as opposed to THC which were weakly correlated with the reducing power. (C) 2003 Elsevier Ltd. All rights reserved.