International Journal of Science, Engineering and TechnologyAuthors: Dr. Ekata Singh
Abstract: One of the most widely consumed psychoactive substances worldwide is caffeine, which is present in coffee, tea, carbonated beverages, and energy drinks. The determination of caffeine content in commercially available drinks is an important activity for quality control, regulatory compliance, and consumer awareness. The present investigation presents and validates a simple, rapid, inexpensive UV–Visible spectrophotometric method for detection of caffeine in commercially available beverages. Standard caffeine solutions were prepared and scanned in the ultraviolet region to identify the maximum absorption wavelength (λmax), and then calibrated in an appropriate concentration range following Beer–Lambert’s law. Commercial samples including soft drinks, energy drinks, tea infusions, and coffee beverages were degassed or filtered as required and subjected to data analysis after appropriate dilution. The linearity, precision, accuracy, limit of detection (LOD), limit of quantification (LOQ), and recovery of the suggested method were analyzed. The linearity of samples across the concentration range was good; recovery and precision were acceptable and therefore suitable for routine quality checks. In the analyzed beverages, the highest caffeine concentration was detected in energy drinks and coffee samples, while the lowest concentration was detected in soft drinks. The method provides a low-cost comparable analytical solution which can be used in a screening procedure and the teaching of laboratories in which advanced chromatographic instruments are not available. Finally, extensive comparative validation with high-performance liquid chromatography is suggested to verify generalization in complex beverage matrices.
