Comparison of the antioxidant activity of commonly consumed polyphenolic beverages (coffee, cocoa, and tea) prepared per cup serving

In this study, the in vitro low-density lipoprotein oxidation model was use d to assess the relative antioxidant activity of the polyphenolic beverages tea, coffee, and cocoa on a cup-serving basis. The beverages were prepared as 0.7-2.5% soluble coffee and 1.5-3.5% cocoa; teas (green, black, or herb al) were prepared as one tea bag infused over 5 min in 220 mL of hot water. Under these standard cup serving conditions, the antioxidant activity as d etermined by the lag time was in the range of 292-948 min for coffee, 217-4 44 min for cocoa, 186-338 min for green tea, 67-277 min for black tea, and 6-78 min for herbal tea. Addition of milk did not alter the antioxidant act ivity. The influence of coffee bean source and degree of roasting was furth er investigated. Green coffee beans of Robusta coffee exhibited a 2-fold hi gher antioxidant activity than Arabica coffee, but after roasting this diff erence was no longer significant. In conclusion, these commonly consumed be verages have a significant antioxidant activity, the highest being soluble coffee on a cup-serving basis.