Determination of Caffeine Contents in Soft Drinks by High Performance Liquid Chromatography (HPLC) Method

Soft drinks have evolved from traditional herbal tinctures into scientifically formulated beverages designed to enhance physical and mental performance. In this study, caffeine, the primary active ingredient in soft drinks, was analyzed using the HPLC-UV method across 15 different commercial products in Türkiye. The caffeine content of most soft drinks was below the legal limit of 150 µg/mL, and caffeine was not detected in some products, and a single drink contained caffeine slightly above the legal limit. For example, Brands 1, 4 and 7 had the caffeine contents of 131.72, 154.38 and 714.64 µg/mL, respectively. The ability of caffeine to block adenosine receptors and enhance intracellular cAMP levels boosts its performance-enhancing effects, including improved endurance, increased alertness, and accelerated fat metabolism. However, risks associated with high-dose consumption, such as elevated blood pressure and reduced ergogenic benefits at doses above 9 mg/kg, require the need for moderated use. This study aims to determine the caffeine content of a variety of energy drinks sold in Turkey and compare these levels against legal thresholds. In addition, it presents validation data for the HPLC method to confirm analytical reliability.