The effect of pectin and other constituents on the antioxidant activity of tea

The effect of pectin on the antioxidant capacity and phenolic content of black, green, mountain tea and Pelargonium purpureum infusions was investigated. Antioxidant capacity was determined by the Ferric Reducing Antioxidant Power (FRAP) assay and total phenolics by the Folin-Ciocalteu method. Green tea was the richest in phenolics and had the highest antioxidant capacity, followed by black and the remaining two infusions. High methoxy pectin, added at various concentrations, did not affect the studied properties of all the infusions. As a further step, milk, lemon juice or sugars (sucrose, fructose) were added to black and green tea infusions, in the presence and absence of pectin. For green tea infusions, no significant differences were reported for the studied properties, for all the constituents, both in the presence and absence of pectin. For black tea infusions statistically different values were observed when pectin was combined with the constituents. These results suggest that pectin does not mask the antioxidant capacity of tea infusions and therefore, it may be added to tea infusions for stabilizing or thickening reasons and create new food formulations with improved health benefits. (C) 2013 Elsevier Ltd. All rights reserved.