Effect of fermentation on the quality of conilon coffee (Coffea canephora): Chemical and sensory aspects

The potential impact of fermentation on coffee quality has been the target of several scientific studies. In this perspective, we present a design of different fermentation processes applied to coffees of the Coffea canephora var. conilon. Thus, coffee samples were submitted to six fermentation methods, at five different times (24, 48, 72, 96, and 120 h). Sensory analysis and hydrogen nuclear magnetic resonance (1H NMR) were used in roasted coffees, to understand aspects of quality and chemical profile, respectively. Variable selection by Fisher discriminant (FD), and multivariate data analysis, including principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and support vector machine (SVM) were used to extract the main chemical information and establish direct relationships with coffee sensory quality. The results indicated chlorogenic acids, caffeine, γ-butyrolactone, lipids, sugars, and acetic acid as responsible for the discrimination of the different fermentation processes. In addition, lipids were characteristic in coffees with higher sensory scores, indicating they are an important marker for the quality of the beverage.