Effect of Drying Methods and Load Volume on Microbial Contaminants and Cup Quality of Arabica Coffee

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Andres A. Basalong Von Y. Amado Hazen Lyn B. Talbino


The effect of drying on bare concrete, portable drying beds, greenhouse-type dryer, and mechanical dryer at 10kg load/m2 and 20kg load/m2 of parchment coffee were assessed for microbial including ochratoxin A (OTA) contamination and cup quality. The shortest drying time of 40 hours was attained by mechanical drying. However, under sun drying, the shortest drying duration was attained from greenhouse-type dryer. Most microbial contaminants were isolated on the parchment coffee dried in all drying methods. Some were still associated on the green coffee beans but none on those dried in the greenhousetype dryer. The fungal species identified were Penicillium sp., Saccharomyces cerevisiae, Fusarium xylariodes, Cladosporium cladosporioides, Aspergillus ochraceus, Aspergillus niger, Fusarium oxysporum and Mucor sp. The dominant fungal species were Penicillium sp. and Saccharomyces cerevisiae. OTA was found on the parchment coffee dried by mechanical dying at 10kg load/m2 and on bare concrete and portable drying beds at 20kg load/m2. However, OTA was not detected in the green coffee beans. All the drying methods except for the bare concrete, produced specialty coffee while coffee dried at 10kg load/m2 had better cupping quality.

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