Caffeine and vitamin B6, a natural occurring compounds and also dietary supplement is widespread in foods of both plants (herbals) and beverages, over consumptions of these two analytes pose health risks to humans. In this study, the levels of caffeine and vitamin B6 in beverages, energy /soft drinks and herbal products were determined using spectrophotometry technique at 272 and 290 nm respectively. Twelve samples of commonly consumed products were selected for analysis. The results of the analyses showed that all the selected samples contained caffeine and vitamin B6. The ascending order of caffeine and Vitamin B6 concentration in the samples analyzed were found as follows: Fajik flusher herbal mixture < Power horse < Coca-cola < Yoyo bitters herbal mixture < Pepsi- cola < Ribena < Top tea < Lipton tea < Red bull < Lucozade boost < Oroki Herbal mixture < Bournvita while Vitamin B6 were: Power horse < Red bull energy drink < Lucozade boost < Pepsi- cola < Ribena < Coca-cola < Lipton tea < Top tea < Fajik flusher herbal mixture < Yoyo bitters herbal mixture < Oroki Herbal mixture < Bournvita. The proposed method was validated in terms of linearity, sensitivity (limit of Detection (LOD)and limit of Quantification (LOQ)) accuracy (% Recovery), precision (relative standard deviation). The method was linear from (4-20 µg/ml and 50 µg/ml-250 µg/ml respectively. (r2 = 0.9991 and 0.9996) vitamin B6 and caffeine respectively. The accuracy (percentage recovery was 99.48 % - 101.42 % for caffeine and 101.85 % - 102.35 % for vitamin B6). The detection limit and quantification limit were 0.192 µg/ml and 0.640 µg/ml for vitamin B6 and 0.0155 µg/ml and 0.0518 µg/ml for caffeine respectively. The method was also found to be precise as the percentage relative standard deviation was below 5%. Therefore, the method proposed in this study is rapid, suitable and can be used as a quality control index for caffeine and vitamin B6 in beverages, energy/soft drinks and herbal products in industries.
Key words: Keywords: Caffeine, Vitamin B6, Beverages, Energy/Soft drinks, Herbal products, Spectrophotometry.
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