Evaluation of Adulteration, Caffeine Content, and Antioxidant Activity in Different Black Tea Brands

Abstract

Tea established as a refreshing stimulant beverage rich in caffeine, sugars, lipids, and aromatic substances demonstrates a wide variation in the quality depending on the type of brand. In this study, five different black tea market brand samples collected from the local market were evaluated for adulterants, caffeine content, and antioxidant activity. Based on the laboratory tests, artificial colors, azo colours, and sand was detected in 80% of tea samples. Caffeine content was determined by the chloroform method. The tea samples exhibited a wide range of antioxidant activity (3.29±1.03 to 15.96±1.2) assayed by the DPPH free radical scavenging method. These investigations could go a long way in promoting the production of quality foodstuff in the larger interest of consumers.