Microbial fermentation affects sensorial, chemical, and microbial profile of coffee under carbonic maceration

In view of the possibility of diversifying metabolic routes promoted by fermentation, this study proposed a new processing method for coffee, which consists of adapting a technique already consolidated in winemaking, carbonic maceration. The assay occurred under anaerobic conditions with different time and temperature fermentation. The aim of this study was to determine the differences in coffee characteristics (sensorial, chemical, and microbial) after carbonic maceration and fermentation. Specialty Coffee Association protocol, nuclear magnetic resonance, and denaturing gradient gel electrophoresis were used in these analyzes. A significant functional relationship between global score and temperature (38 degrees C), for the fermentation time of 96 h was observed. Bacterial diversity and sensory characteristics had a positive correlation. Furthermore, trigonelline, formic acid, hydroxymethylfurfural, lipids, and gamma-butyrolactone also contributed to score and sensory quality of coffee beverage. Thus, our data show consistent factors to infer on the microbiological action on the sensory quality of coffee beverage.

Automated summary

This study introduced a new processing method for coffee using carbonic maceration, which showed a significant functional relationship between global score and fermentation temperature of 38 degrees Celsius for 96 hours. Bacterial diversity had a positive correlation with sensory characteristics, and compounds like trigonelline and formic acid contributed to the sensory quality of coffee beverage. This data provides insights into the microbiological action on the sensory quality of coffee beverage.