The Influence of Temperature and Air Velocity on the Hot Air Drying of Cocoa Bean

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Juntima Chungsiriporn
Prukraya Pongyeela
์Nirana Chairerk


The objective of this research was to investigate the effects of drying parameters on drying time and specific energy consumption of cocoa beans drying. The drying temperature of 50, 60, 70 and 80oC and air velocities of 0.05, 0.067, 0.085 and 0.1 m/s were studied. Amount of cocoa bean placing on drying tray at 1 and 2 layers were monitored. The moisture ratio, drying rate and energy consumption were analyzed. The results showed that the drying time decreased as the drying temperature and the air velocity increased. The optimum condition for drying cocoa beans was at 60oC with air velocity of 0.1 m/s at 1 layer of bean drying. The drying time of 130 min, which was the lowest energy consumption condition as the specific energy consumption of 74 MJ/kg water evaporated. The Midilli et al. model was an equation that predicts the optimum reduction of cocoa bean moisture. The highest decision coefficient (R2) and the lowest RMSE, and SSE with R2 greater than 0.9964 RMSE and SSE value were 0.01774 and 0.000913, respectively. These results can be used as a guideline for further development of cocoa bean drying quality.

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Chungsiriporn, J., Pongyeela, P., & Chairerk ์. (2023). The Influence of Temperature and Air Velocity on the Hot Air Drying of Cocoa Bean . Journal of Engineering, RMUTT, 21(1), 11–20. Retrieved from
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