LAUSR

Abstract Coffee is an important agricultural commodity worldwide. Its quality is influenced by several factors that can damage kernels, changing the product composition, flavor, appearance, and causing weight loss. Mathematical models for estimating the dry matter loss of coffee were not found in scientific literature. This study deals with the calibration and validation of a model for predicting the dry matter loss of coffee beans under different storage times, temperatures and moisture contents. For this, green parchment grain of Coffea arabica (cv Catuai Vermelho) were used. Measured dry matter losses varied from 0 to 1.2% and the proposed model was accurate when comparing experimental and predicted data (99.8%). Mean bias, absolute and relative errors were −0.001%, 0.026% and 13.6%, respectively, while the root mean square error was 0.066%, evidencing low scattering and high precision. The estimated maximum allowable storage times of coffee beans, based on a 0.5 dry matter loss threshold, varied from 9 years (for temperature and moisture content of 15 °C and 14% d.b.) to 2 days (for temperature and moisture content of 35 °C and 22% d.b.). The proposed model can be easily implemented in computer programs, appearing as an important tool when simulating the drying or aeration processes, as well as for helping in decision making for coffee storage and trading.