Pectinase-assisted fermentation of mucilage removal from Coffea liberica

Coffea liberica comprises 73% of coffee population in Malaysia. However, its consumption is relatively low. In post-harvesting, perfect coffee fermentation is characterized by the release of mucilage surrounding coffee beans and takes more time to complete mucilage removal. Mucilage naturally be fermented by endogenous bacteria through wet fermentation. By using pectinase enzyme, mucilage that is composed of pectin can be removed in short period of time. This study was conducted to determine the optimal pectinase-assisted fermentation duration of mucilage removal of Coffea liberica and the quality attribute by antioxidant and total phenolic compound (TPC) of roasted Coffea liberica in different fermentation periods. Samples preparation started with depulped coffee beans and soaked in pectinase enzyme solution for 4, 6, 8 and 10 hours. Mucilage degradation was observed from the pectin content (%). Antioxidant activity was measured using Ferric Reducing Antioxidant Power (FRAP) and 2,2-diphenyl-2-picrylhydrazyl (DPPH) assays while TPC was using Folin-Ciocalteu method. The results showed the pectin content (%) at 8 hours of pectinase-assisted fermentation was 38.11% lower than control. It gave the highest content with 129.89±0.007 mg GAE/100g and showed significant difference (p<0.05). Antioxidant activity measured through FRAP and DPPH continues to decrease across time. In conclusion, pectinase-assisted fermentation was found to reduce the time required for mucilage removal, with an optimal duration of 8 hours. Pectinase-assisted fermentation also impacts of roasted coffee beans by increasing TPC but reducing the antioxidant activity by FRAP and DPPH assays with prolonged fermentation.