In addition, the caffeine content in each brewed coffee sample was determined by (C18)SPE-UV/HPLC. RPHPLC/UV has already been applied by other authors for caffeine determination in green coffee beans (Barre et al., 1998) and cola beverages (Theodoridis and Manesotis, 2002). SPE has been adapted to extract caffeine from coffee extracts for HPLC determinations according to Theodoridis and Manesotis (2002).