Aqueous extract of citrus peel reduces production of hydrogen peroxide in catechin-enriched green tea

Hydrogen peroxide (H2O2) is gradually produced in bottle-packed beverages, including tea and coffee, after the cap has been opened, i.e, through exposure to air, though only a small amount of H2O2 is detected in the beverage immediately after the bottle is opened. Since, H2O2 is toxic, it is necessary to develop safe and simple ways of reducing its production in bottled beverages. The addition of an aqueous extract of citrus peel reduced the concentration of H2O2 in green tea. To characterise the active constituents in the citrus peel, the aqueous extract of the peel was fractionated using chloroform, ethyl acetate, and butanol, in that order, and subjected to gel chromatography. The active constituents in the citrus peel were water-soluble compounds of various molecular weights.