Antioxidant properties of commercial alcoholic and nonalcoholic beverages.

Recent interest in food phenolics has increased greatly, because of their antioxidant and free radical scavenging abilities. Popular beverages in the world include tea, coffee, cocoa, beer, wine and fruit/vegetable juices. All of these beverages contain phenolic compounds. In present study total polyphenol content and in vitro antioxidant properties were investigated in 16 red wines, 5 white wines, 5 lager beers, 3 dark beers, 17 fruit juices and 5 vegetable juices. High polyphenol content was measured in red wines (1720 +/- 546 mg x L(-1)) and in some fruit juices such as elderberry and prunes (5,680 and 1,807 mg x L(-1), respectively). The concentration of polyphenols was between 159 and 5,680 mg x L(-1) in fruit juices and between 255 and 696 mg x L(-1) in vegetable ones, while low level of phenolics was observed in dark and lager beers and white wines (473, 376 and 392 mg x L(-1), respectively). All samples exhibited significant antioxidant properties such as hydrogen-donating ability, reducing power, chelating ability and total antioxidant status (TAS) value. These antioxidant properties strongly correlated with the total polyphenol content of the beverages.