Volatilome of fermented and roasted Coffea arabica in Brazil: a systematic review of the influence of microbiota and fermentative processes.

Coffee is widely consumed worldwide and recognized for its sensory complexity, resulting from the interaction among genetic, environmental, and post-harvest processes. Fermentation is a critical stage that directly influences coffee's aromatic profile and is a topic of growing research interest. However, integrative analyses of how microorganisms and processes affect the volatilome are still required. This systematic review aimed to synthesize and analyze existing evidence on the formation of volatile compounds in fermented and roasted Coffea arabica, emphasizing comparisons among fermentation processes, inoculated or not, and their implications for diversifying coffee's aromatic profile. Twenty-one studies were compiled and analyzed. The review identified 340 distinct volatile compounds, belonging to classes such as alcohols, esters, furans, and pyrazines, which contribute to desirable sensory notes, including fruity, floral, and caramelized. Co-inoculation stood out for expanding the diversity of volatile compounds, offering a promising tool for customizing coffee's aromatic profile. The results indicate that induced fermentation processes, especially anaerobic ones, positively influence volatile formation, while co-inoculation can be an effective strategy for optimizing sensory quality. This review contributes to understanding how fermentation can be conducted to obtain differentiated coffees with enhanced sensory value.