Comparative HPLC and GLC determination of caffeine in different food products

Abstract Two chromatographic (HPLC and GLC) methods are described for direct analysis of caffeine, and some related xanthine derivatives in various kinds of food products and beverages. For HPLC, a 10 uC18 reverse phase column and for GLC, a non polar OV17 column were used. Caffeine and/or other alkaloids are effectively extracted with CHCl3 containing 5% isopropanol from NH4OH alkalinized prepartions. The extract was used for direct analysis by any of the proposed methods. Better resolution and more sensitivity are achieved by the HPLC procedure. Detectability in both HPLC and GLC is at the nanogram levels and the two methods can be applied for caffeine determination in decaffeinated products as well as in minicoffee tablets and in beverages.