Effect of Infusion Time and Temperature on Decaffeination of Tea Using Liquid–Liquid Extraction Technique

Abstract

Abstract Pure caffeine was dissolved in four different solvents, i.e., distilled water, ethyl acetate, chloroform and dichloromethane; further, molar decadic absorption coefficient of each solvent was determined with the help of B eer– L ambert law. It was observed that dichloromethane was the best for decaffeination as compared with the other three solvents (i.e., distilled water, chloroform and ethyl acetate). Caffeine was extracted using dichloromethane from five famous tea brands, namely A lokozay, L ipton, T apal, T etley and PG TIPS . The amount of extracted caffeine was quantified by employing UV ‐vis spectrophotometric technique. The concentration of the caffeine in the tea solution was determined at different brewing time (2, 5, 10, 15, 20, 25 and 30 min) and temperature (90 and 30C). The caffeine contents in the commercial brands (i.e., A lokozay, L ipton, T apal, T etley and PG TIPS ) were found in the range between 1 and 5%. Practical Applications Caffeine becomes an important issue because of its utilization in pharmaceuticals. It is also an eminent fact that excessive amount of caffeine can be dangerous to human health. In addition, tea is one of the main sources of caffeine for human body. So, the present experimental studies are mainly focused to quantify and reduce the caffeine contents using a cost‐effective, accurate and precise way. For this purpose, an analytical technique, i.e., UV ‐vis spectrophotometry, used to determine the caffeine contents and solvent extraction process was employed to extract the caffeine from its tea aqueous solution.