Comparative contents of some phenolics in beer, red and white wines

It is generally assumed that the higher the total polyphenols content of a beverage, the greater is its antioxidant activity. Our previous experiments bn laboratory animals and clinical investigations showed that the content of total polyphenols is higher in white wine than in beer, but beer possessed a higher antioxidant activity. In order to find the sources, which determine the degree of the antioxidant activity the comparative content of some important phenolics in beer, red and white wines was examine. Total polyphenols, procyanidins, epicatechin, quercetin, ferulic, p-coumaric and gallic acids were determined in these beverages. The content of total polyphenols was significantly higher in red wine than in white wine and beer (p < 0.0025 in both cases). Similar relationship was found for procyanidins, epicatechin, and quercetin, ferulic, p-coumaric and gallic acids (p < 0.0005 in most cases. The contents of total polyphenols and quercetin were significantly higher in white wine than in beer (p < 0.0125 and 0.01, respectively). But the contents of procyanidins, epicatechin and ferulic acid were statistically significant higher in beer than in white wine (p < 0.005, p < 0.05 and p < 0.0025 respectively). The higher contents of procyanidins, epicatechin and ferulic acid in beer is a possible explanation of the marked antioxidant activity of diets supplemented with this beverage rather than with white wine in our experiments on laboratory animals. (C) 1999 Elsevier Science Inc.