Ultraviolet-Visible Spectrophotometric Determination of Caffeine in Different Tea Samples

Abstract

Martins Moses, Andy N.M., John Stanley, Muslim U. Abdullahi, Benjamin Biko, Silas, Ishaku, Adam Aliyu and Christiana O. Albert

Caffeine (1,3,5-trimethylxanthine) contents fromseventeen brands of black and green tea that are common in Yobe State, Nigeria were extracted and analysed for their concentration usingan Ultraviolet-Visible spectrophotometer. The results indicated caffeine concentration in the range of 347ppm (in Akbar tea) to 770 ppm (in Sultan tea). The relative concentration of caffeine in the analyzed samples ranked as follows, Sultan (770 ppm) > Lipton yellow label (733 ppm) > Amar (728 ppm) > Shams Green Tea (712ppm) > Tea Pot (699 ppm) >Ahdar (670 ppm)> Nana Tea (666 ppm) > Apple Black Tea(649 ppm)> Ahmed Tea(639 ppm) > Lipton Clear Green (599 ppm) > Tea Shop (564ppm)> Tetley (553 ppm) > Accord (508 ppm) > Tiger (388 ppm)> Top Tea (378 ppm)> Beyond Comment (365 ppm) > Akbar (347ppm). The caffeine contents in the tea samples analyzed in this study were below the maximum recommended limits for consumption and may not present an immediate health challenge except if excessive consumption is administered within a short period.