The influence of decoction and infusion methods and times on antioxidant activity, caffeine content and phenolic compounds of coffee brews

This study was performed to compare the effects of brewing method (decoction and infusion), time (1-5 min), and also origin of coffee beans on antioxidant activity using DPPH, ABTS, FRAP methods, caffeine content and phenolic compounds by HPLC. Principal component analysis was used to determine the effective treatments on bioactive properties. Coffee brews prepared with decoction method contained higher contents of total phenolic, total flavonoid, and total tannin as compared to the infusion method. On the other hand, antioxidant activity of coffee brews by DPPH and ABTS radical methods showed an opposite trend. Similar to antioxidant activity, infusion method was better to obtain higher amounts of catechin, caffeic acid and quercetin in coffee brews. The brewing method did not cause a significant difference in caffeine and rutin contents. Brewing time had major effects on several bioactive compounds, and their amounts showed an increase after extending the time of brewing.