Volumetric shrinkage and shape of Conilon coffee fruit (Coffea Canephora)

Abstract

The effect of varying the water content was evaluated in shrinkage, dimensional characteristics and shape of the fruits of coffee during drying. Fruits were used Conilon coffee (Coffea canephora), clone 83 of clonal variety EMCAPA 8141. The fruit was hand-picked and selected only the two stages, cherry and unripe. Different batches of coffee were dried in an oven with forced ventilation with air temperature of approximately 60 ± 3 °C until different levels of water content. Fruit size was determined by varying the volume and shape was examined by sphericity and roundness. The shrinkage of the fruits was determined by the ratio between the volume at each water content and initial volume. It was determined that the projected area, surface area and volume increase with increasing water content for conilon coffee fruit. The shape of the conilon coffee fruits was influenced during the drying process, promoting the decrease of sphericity and roundness values from the reduction of water content. The shrinkage showed a nonlinear behavior with decreasing reducing the water content of the mass of Conilon coffee fruit. The polynomial model represented satisfactorily phenomenon of unit volumetric shrinkage and mass of coffee fruits depending on the water content.