Impact of microbial self-induced anaerobiosis fermentation (SIAF) on coffee quality

The fermentation of natural (NC) and pulped coffee (PC) was performed with a conventional method (platform) and under self-induced anaerobic fermentation (SIAF). Of the 12 samples analyzed during the fermentation process, the highest temperature was obtained by the SIAF method (30.5 °C for NC and 29.67 °C for PC) with 87 h of fermentation. Nonvolatile compounds (36 samples) were evaluated by high-performance liquid chromatography. Fermentation in the SIAF method contributed to the maximum amount of citric acid (2.534 mg/g) in pulped coffee and acetic acid (6.04 mg/g) and lactic acid (2.533 mg/g) in NC. Furan was the primary chemical class detected, followed by ketones and pyrazines. All coffees (12 samples) were evaluated five times and classified as specialty coffees (>80 points) following Specialty Coffee Association (SCA) protocols. The pulped coffee processed by the SIAF method showed a 2.83-point increase in the sensory score compared to the conventional method. Therefore, the SIAF method is accessible to producers, contributes to coffees with differentiated sensory profiles, and increases beverage quality. • Coffee fermentation under self-induced microbial anaerobiosis (SIAF). • The internal temperature increased significantly with the use of the bioreactor. • Higher levels of lactic acid were detected in controlled fermentation. • The use of the bioreactor increased the sweetness, acidity, and body of the beverage. • The optimized bioreactor can guarantee a better quality of the beverage.