Effects of brewing conditions on total phenolic content, antioxidant activity and sensory properties of cascara

Abstract

The processing of coffee cherries into coffee beans produced a lot of residues, particularly coffee pulp, which can be further valorized to produce valuable bioproducts, one of which is cascara. This study was carried out to determine the effects of brewing conditions (brewing temperature, time, and addition of propolis) on total phenolic content and antioxidant activity of cascara. An organoleptic test was also carried out to determine the sensory properties of cascara. Cascara had a higher total phenolic content when brewed using a hot brew method. Increasing the brewing temperature from 70 to 90 °C reduced the antioxidant activity while increasing brewing time from 4 to 8 min increased the total phenolic content of cascara. The optimal conditions for brewing cascara based on the developed regression model were hot brewing at 77 °C for 8 min without additional propolis, with an antioxidant activity IC50 and total phenolic content of 432.87 ppm and 2.07%, respectively. The addition of propolis caused a decrease in the antioxidant activity and total phenolic content of cascara. Based on the results of the organoleptic test, the panelists preferred cascara that was brewed without the addition of propolis because it had a fresher, sour taste.