Aroma profiles and cupping characteristics of coffee beans processed by semi carbonic maceration process

Abstract

The goal is to improve the flavors of Arabica coffee by combining semi-carbonic maceration (SCM) process, with enzymatic process at various lengths and temperature. Five different variations of SCM processes were investigated: pulped natural process (control); at 15 o C for 10 days (SCM-15); at 20 o C for 10 days (SCM-20); with 0.01 g.L -1 pectinases A (polygalacturonase, pectin esterase and pectin lyase); at 20 o C for 5 days (SCM-PA); and with 0.03 g.L -1 pectinases B (polygalacturonase, pectin esterase, pectin lyase and ß-glucanase) at 20 o C for 5 days (SCM-PB). The chemical composition of intact mucilage and green bean coffee were analyzed. The environments created by using SCM fermentation process at 20 o C combined with pectinase A and pectinase B produced green bean coffee with higher content of acidity and reducing sugar. The volatile compounds of roasted coffee were examined by Gas Chromatography-Mass Spectrometry (GC-MS). Fifty-one volatile compounds belonging to 12 chemical classes were identified. The different total peak area, indicates that most volatile compounds, increases during SCM, and SCM process combined with enzymatic method. The Specialty Coffee Association of America; SCAA sensory analysis was performed by ten trained specialty coffee judges. The final product of coffee beans, which has been treated with SCM process at 15 and 20 o C have obtained the highest score in fragrance, flavor, aftertaste, body, balance and overall impression. While the enzyme treatment has attained the highest scores in acidity. This study demonstrates that the proposed process may be useful for the improvement of the cup quality.