Mould species infestation during sun drying of sound and split coffee cherries

Drying procedures for robusta coffee commonly applied by farmers in Java, Indonesia are sun drying of sound and split cherries. The second procedure is applied in some areas to shorten the drying time. An experiment on both procedures was conducted on the ground, a patio, and on a plastic sheet with 3 and 6 cm thickness. Each treatment was conducted in 3 replications. The development of moulds during drying was analysed by the direct plating procedure on the DG-18 media. The dominant species observed in the beans were Aspergillus niger, A. flavus, Penicillium citrinum, and A. ochraceus. A few other minor species were also observed. Coffee splitting resulted in lower contamination rate in A. ochraceus. Freshness and maturity of coffee cherries determined mould contamination status during drying. The contamination rate of mould species even when drying treatments are employed is discussed.