AN INVESTIGATION OF THE ANTIOXIDANT ACTIVITY OF BLACK TEA USING ENHANCED CHEMILUMINESCENCE

Antioxidants are important species which possess the ability to protec t the body from damage caused by free radical-induced oxidative stress . A variety of free radical-scavenging antioxidants exist within the b ody many of which are derived from dietary sources. There is currently much interest in the antioxidant role of flavonoids and other polyphe nols found in tea, wine, fruit and vegetables. Enhanced chemiluminesce nce is a simple technique which can be used as a rapid and sensitive a ssay for measuring the antioxidant activity of beverages such as green and black tea. This article examines the impact of water temperature, stewing time, leaf concentration and the addition of milk upon the an tioxidant activity of black tea solutions. The antioxidant activity of a range of commercially available black and green teas has also been measured.