• QA 022
    How to avoid parchment over-drying and loss of colour in dry, hot conditions?
    Our harvesting season coincides with our winter when conditions usually are very dry with clear skies and strong sunshine. This sometimes results in quite high temperatures, causing coffee to dry too rapidly and to lose colour. We are not sure that the Colombian drying system shown in 11.05 would help here; in fact it might even make things more difficult for us?
    Asked by:
    Grower - Zambia

    We recommend you consider shading the drying area, using shade cloth over a frame. The frame should be high enough for staff to walk underneath and you should include the possibility of rolling the shade cloth aside in case of dull cloudy conditions. The shade cloth will lower the temperature whilst allowing air to circulate. This will slow the drying process and help to even it out, thereby also safeguarding colour. Of course you will have to experiment first with different densities of shade cloth to determine the optimal degree of shade. Also, ensure that subsequent parchment conditioning and storage takes place in in a reasonably cool environment, i.e. in a well-ventilated, well-constructed warehouse.

    We agree with you that the winter season in Southern Africa does produce quite hot and dry conditions, often coupled with wind, which cause too rapid drying and loss of colour. Under these circumstances drying under a plastic cover is not needed because there is no rain, whereas the heat build-up might at times become excessive.

    For more see 11.05 Preparing high quality arabica - the Green.

    Posted 27 May 2005

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