Impact of Altitude and Fermentation Temperature on the Quality of Panamanian Geisha Coffee

Premium Panamanian Geisha coffee is renowned for its exceptional sensory quality, yet the environmental and processing factors underlying these attributes are not fully understood. This study evaluated the effects of altitude and fermentation temperature on the sensory and physicochemical properties of Coffea arabica var. Geisha. Coffee cherries from four farms at different altitudes in Chiriquí, Panama, were fermented under three temperature conditions (ambient farm temperature ~19 °C, 24 °C, and 30 °C). Sensory evaluation was conducted by professional cuppers, while brewed samples were analyzed for chlorogenic acids, caffeine, pH, soluble solids, total acidity, polyphenols, and antioxidant activity. Coffees grown above 1700 masl achieved significantly higher cupping scores (87–90 points) compared to those from lower altitudes (86–87 points, p < 0.01). High elevation was associated with increased chlorogenic acids and reduced caffeine, Total soluble solids, and pH. Fermentation at the cooler ambient temperature yielded superior sensoryscores relative to 24 °C and 30 °C treatments (p < 0.05). Principal component analysis confirmed altitude as the dominant factor shaping sensory quality, while classification tree analysis identified brew pH as the most influential physicochemical predictor. Altitude alone explained ~72% of the variance in sensory quality, and models integrating key chemical variables increased explanatory power to 75–78%. Results demonstrate that high-altitude cultivation combined with cooler fermentation enhances Geisha coffee quality. Future research should integrate soil properties, shade management, and microbial profiling to strengthen predictive models and optimize production strategies for this globally prized variety. Key words: Cup quality; decision tree; multivariate analysis; specialty coffee.