Rapid High-Performance Liquide ChromatographicMethod for Quantitative Determination of Caffeine in Different Soft and Energy Drinks Available in Bangladesh

Caffeine is one of the commonly used food additives, which has unique flavor characteristics and bitter taste and used in soft drinks as flavor enhancer. An experimental study was designed to determine the concentration of caffeine in different brands of soft drinks and energy drinks available in Bangladesh by using HPLC. For chromatographic analysis, A Luna 5 mu C18 (2) 100A column (250x4.6 mm) was used at 37 degrees C temperature at the wavelength of 272nm. Chromatographic separation was determined using buffer of sodium acetate and acetic acid with acetonitrile at a ratio of 80:20 (pH=4.0; flow rate of 1.0 ml/min).The results of this study showed that caffeine content in soft drinks ranged from 19.63 to 101.73 mg/100ml and highest concentration of caffeine found in brand 3 samples while lowest concentration found in brand 2 samples. Significantly higher concentration of caffeine (p<0.05) found in six soft drinks sample when compared to BSTI and FDA reference value except brand 2 sample (p>0.05). Quantification of caffeine in different brands of energy drink sample revealed that, four brand sample contained caffeine; among them brand 3 sample showed the highest levels of caffeine 295.86 mg/100ml and lowest amount found in brand 1 sample (101.74 mg/100ml). Concentration of Caffeine in soft and energy drinks exceeded the national and intemational standard recommended range hence this proposed HPLC method can be used for routine determination and control of caffeine content in different drinks.