Comparative analysis of drying coffee beans using microwave and conventional oven




grain drying, drying curve, diffusion coefficient, microwave drying


This article reports a comparative study of experimental results obtained during the drying of Castilla-variety coffee beans from Santander, Colombia. They were performed by two means: thermal and electromagnetic radiation. Twenty experiments were carried out, ten tests in a microwave cavity at 2,450 MHz-1,080W, and ten tests using a conventional electric oven with temperature controlled at 50±2oC. Experiments were made using samples of coffee beans with parchment, without parchment, and of the only-parchment. For each sample, dimensionless moisture ratio and diffusion coefficients were determined, according to the second law of Fick. We found that the diffusion coefficient of the samples dried in a microwave cavity was twenty-two times higher than the diffusion coefficient of samples dried with thermal radiation. Likewise, it was observed that samples in conventional oven showed a uniform temperature, in contrast with those heated by microwave radiation. Such results are useful for designing hybrid systems for drying coffee beans.

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Author Biographies

Manuel Fernando Roa-Ardila, Industrial University of Santander

Doctoral student in Materials Engineering.

Carlos Rodrigo Correa-Celi, Industrial University of Santander

Professor, PhD. Polymer Science And Engineering (Lehigh University).


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How to Cite

Muñoz-Neira, M. J., Roa-Ardila, M. F., & Correa-Celi, C. R. (2020). Comparative analysis of drying coffee beans using microwave and conventional oven. Revista Facultad De Ingeniería Universidad De Antioquia, (95), 100–108.

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