Effect of altitude on coffee (Coffea arabica L.) quality: comparison between mechanical and traditional drying

Coffee is one of the most widely consumed beverages in the whole world. The drying process for the storage of coffee beans is decisive for the physical and sensory characteristics of the final product. The objective of this study was to evaluate the effect of two types of dryers (mechanical and traditional) at five altitudes on coffee quality. The research was conducted in the Alto Mayo valley, San Martin region, Peru. Five farms were selected at different altitudes (873, 1079, 1248, 1348, 1430 m.a.s.l.). The prototype used works through a system of thermal heat tunnels, built with solar micas and calamine. 150 samples of 1 kg were extracted. The variables evaluated were the physical and organoleptic characteristics of the dry grain, as well as the number of drying days. The results showed that there were no significant differences for any parameter evaluated between the selected altitudes. However, there were significant differences for the parameters of humidity and amount of first category grain, where mechanical drying was superior. Also, in the case of organoleptic quality, mechanical drying was presented as the best option, indicating that its use can optimize the organoleptic quality of coffee.