ANTIOXIDANT ACTIVITIES, SUGAR AND CAFFEINE CONTENT IN THAI ARABICA COFFEE BEANS

The antioxidant activities, total phenolic compound (TPC), sugar and caffeine content in Thai Arabica Coffee processed with natural, honey and washed processes were studied. Coffee samples were obtained from the crop between December 2020 to January 2021. The TPC by Folin-Ciocalteu’s Assay was detected in the range of 29.66 - 32.88 mg GAE/g Coffee DW. The Ferric Ion Reducing Antioxidant Power Assay (FRAP) value was found in the range of 52.54 - 73.62 mg, Trolox Equivalent/g Coffee DW. The Half Maximal Effective Concentration (EC50) by 2,2-Diphenyl-1picrylhydrazyl Assay (DPPH) was detected in the range of 1.57–1.82 mg Coffee DW/g DPPH. There was no significantly different in EC50, TPC, and Caffeine between the processes; while the FRAP and sugars were significantly different at p < 0.05. The natural process coffee contained monosaccharides more than the washed process coffee. The FRAP, TPC, Caffeine, Glucose and Fructose values significantly depended on the coffee’s origin (p<0.05).