Commercial yeast fermentation and 7P-Fermaestro® processing: Strategies to improve sensory and chemical qualities in Coffea arabica L. var. Castillo

Abstract

ABSTRACT Controlled post-harvest fermentation is increasingly used to enhance specialty coffee quality by modulating microbial metabolism and sensory differentiation. This work compared controlled fermentation with the commercial yeast Saccharomyces cerevisiae Lalcafé CIMA™ (Lallemand®) for 40 h (LV1-T40) or 60 h (LV1-T60) with the traditional 7P-Fermaestro® process from Cenicafé (F) in Coffea arabica L. var. Castillo. Three treatments were evaluated over three successive harvests under a completely randomized design. Physical quality of dry parchment coffee, sensory attributes according to the Specialty Coffee Association protocol, caffeine, chlorogenic acids, and trigonelline contents by HPLC-DAD, and FT-NIR spectral profiles were analyzed. Initial fermentation conditions were comparable among treatments. Yeast inoculation promoted stronger acidification and soluble-solids depletion, indicating more active fermentation dynamics. Physical quality was influenced mainly by harvest rather than treatment. Sensory analysis showed that fermentation significantly affected fragrance/aroma, flavor, balance, and final SCA score, with LV1-T60 showing the best overall cup performance. Caffeine and chlorogenic acid contents were not significantly affected by treatment, whereas trigonelline was significantly higher in LV1-T60. FT-NIR spectra showed high global similarity among treatments, although chemometric analysis detected subtle treatment-related variations. Overall, 60 h yeast-assisted fermentation improved cup quality while preserving physical quality and producing moderate chemical changes.