Spectrophotometric determining of caffeine content in the selection of teas, soft and energy drinks available on the Croatian market

Abstract

This study aimed to determine concentrations of caffeine in the samples of the selected brands of teas, soft carbonated and energy drinks that are commercially available on the Croatian market. Quantitative analysis of caffeine content in the chosen beverage samples was done with UV/Vis spectrophotometric method. Chloroform was used as the solvent and concentrations of caffeine were measured at the wavelength of 274 nm for three samples of each of the selected beverages. Among the analyzed tea samples the highest caffeine concentration was found in Franck's Black Tea (1471.021 ppm) and the lowest in Naturavita's Green Tea with Ginger (588.138 ppm). Between the analyzed carbonated soft drinks, the highest caffeine concentration was measured in Fresh Cola (136.036 ppm) and the lowest in Sky Cola (48.198 ppm). The highest caffeine concentration in the analyzed energy drink samples was measured in Hell energy drink (394.670 ppm) while the lowest was in Coca Cola Energy drink (173.574 ppm). The results of this study gave preliminary information about caffeine levels in often consumed teas, carbonated soft drinks and energy drinks in Croatia. The caffeine content in the analyzed teas and drink samples in this study was under the allowed one except for Red Bull and Hell.