DETERMINATION OF GEOGRAPHICAL ORIGIN OF GREEN AND ROASTED COFFEE BASED ON SELECTED CHEMICAL PARAMETERS

Abstract

Coffee is one of the most consumed beverages in the world. Its quality depends on many factors, such as, country of origin, altitude, climate, post-harvesting processing and others. This paper is focused on the possibility to determinate origin of American, African, and Asian coffees based on chemical properties of the final beverage, such as total antioxidant capacity (TAC) measured using DPPH radical, content of chlorogenic acids and caffeine determined by HPLC-DAD. Samples of green and roasted coffee (roasting level medium dark Full City ++) were used. In green samples the highest values of TAC and caffeine were measured in American samples (averagely 93.014 % inhibition of DPPH and 0.854 g.100 g−1 of caffeine respectively), the highest content of chlorogenic acids showed samples from Africa (averagely 5,037 g.100 g−1). In samples of roasted coffees values of TAC decreased by 7, 47 % in Africa samples, by 18,12 % in American, and 13,73 % in samples from Asia. Roasted African coffees showed on average 1.035 g.100 g−1 of caffeine, the highest average was measured in American samples (1.201 g.100 g−1), and lowest Asian samples (1.089 g.100 g−1). Lowest content of CGAs was obtained from African samples (0.595 g.100 g−1), and the higher from American (0.596 g.100 g−1) and African samples (0.6345 g.100 g−1). ANOVA single factor showed significant differences between green samples regarding the TAC and caffeine content. However, content of chlorogenic acids did not show any difference (p-value=0,6809) regarding the geographical origin. Same results were obtained comparing roasted samples.