Uv-spectroscopic and iodometric back titration analysis of total caffeine content of energy drinks available in markets in cross river state, south-south, nigeria

Abstract

Caffeine is an active ingredient of energy drinks that is often consumed to improve cognizance and physical cum mental alertness. This research aims to quantitatively analyze the caffeine content in serving volumes of energy drinks by spectrophotometric and iodometric back titration methods. In the spectrophotometric method, the determination of caffeine content was carried out using a maximum wavelength of 270 nm. The results show that the caffeine contents of the energy drinks were 37.40 mg/200 mL (Passion) < 64.73 mg/250 mL (Bullet) < 82.70 mg/355 mL (Power Horse) < 86.30 mg/400 mL (Predator) < 114.68 mg/500 mL (Fearless) while the iodometric back titration method showed 57.50 mg/250 mL, 165.00 mg/500 mL, 160.00 mg/400 mL, 117.15 mg/355 mL and 40 mg/200 mL respectively for Bullet, fearless, Predator, Power Horse and Passion. The labeled claims on the energy drinks were 78.75 mg/250 mL, 157.50 mg/500 mL, 120.00 mg/400 mL, 133.60 mg/355 mL and 50 mg/200 mL respectively for Bullet, fearless, Predator, Power Horse and Passion which indicates that manufacturers reported higher values of caffeine content in their product possibly to make it attractive to consumers.