Efeito da fermentação sólida anaeróbica e da altitude nas propriedades físicas, composição química e qualidade sensorial de café arábica

Abstract

This study investigated the effects of anaerobic solid fermentation and altitude on the physical properties, chemical composition, and sensory quality of Coffea arabica beans. The experiment was conducted at two altitudes (980 and 1240 m) and five fermentation times (0, 48, 72, 96, and 120 h). The samples were evaluated for color, apparent bulk density, sugar profiles, organic acids, fatty acids, bioactive and volatile compounds, as well as sensory analysis following the SCA protocol.The results showed that the combination of fermentation time and altitude plays a decisive role in determining coffee quality. Longer fermentations led to decreased density and increased yellowing of the beans, especially at lower altitudes. Despite these physical changes, a significant sensory improvement was observed, with increased sweetness, acidity, and balance, reaching scores above 86 points for 48–72 h fermentations at 980 m. At higher altitudes, sensory variations were minimal, while physical losses became more pronounced, indicating lower economic viability of the process.Chemically, fermentation caused significant changes in organic acids, sugars, and bioactive compounds, with a relative increase in unsaturated fatty acids and variations in caffeine, trigonelline, and chlorogenic acid contents. The differentiated production of volatile compounds confirmed the metabolic reconfiguration induced by the process. It is concluded that anaerobic solid fermentation, when controlled and applied to low-altitude coffees, is an effective strategy to enhance aromatic complexity, sensory quality, and added value of the product; for higher altitudes, however, fermentation did not prove to be a suitable option under the conditions of this study.