Determination of Caffeine in Soft and Energy Drinks Available in Market by using UV/Visible Spectrophotometer

Abstract

This experiment did to determine the pH, levels of caffeine concentration in five soft drinks and four energy drinks available in local market of Pakistan. pH were measured by pH meter. Quantitative estimation of caffeine concentration in drinks was performed by a simple and fast standard UV spectrophotometric method (Perkin Elmer lambda 35 UV/Vis spectrometer) using carbon tetrachloride as the extracting solvent at 270 nm wave length. The minimum caffeine level of soft drinks was observed in Brand-3 (10.69 mg/serving), while Brand-5 showed the highest caffeine content (42.17 mg/serving) showing a range from 10.6 to 42.17 mg/serving. The concentration of caffeine in all energy drink samples are well below the maximum allowable limits set by the food regulatory bodies, except E 2. The E 2 has greater calculated concentration then the labeled concentration .The minimum caffeine level of energy drinks was observed in E 4 (32.04 mg/L) while E 2 showed highest caffeine level in energy drinks (101.705mg/serving) showing range from 32.04 mg/serving to 101.705 mg /serving. And the pH range of these soft drinks were (2.29 to 3.02) and in energy drinks (2.85 to 3.28).