Drying

 
 

Overview

Aim for a drying curve that begins quickly and decelerates across 3 to 4 weeks. Your tools to control drying speed:

Drying Table.jpg
 
 
 
 

 

Gakenke-4289.jpg

Drying Guidelines

  • Sweep and clean drying beds of all foreign matter and old coffee before starting.
  • Begin drying immediately after washing. Do not hesitate.
  • Keep the drying bed below 40°C. This will extend shelf life.
  • Gently turn the parchment hourly during the day with a plastic or wooden rake.
  • If possible, dry on mesh raised beds to allow airflow around the parchment. \
  • Modulate shade and airflow to keep within the desired temperature range.
  • Modulate bed depth to speed up or slow down moisture loss.
  • If nights are cold, pile up the parchment and cover with blankets without strong odours (e.g. cotton, not burlap).
  • Don’t allow the coffee to get wet (from rain or dew) during the drying phase. If it is likely to rain often, preemptively shield the coffee by building a simple roof over the drying beds.


Drying Steps

 

Perla-de-Otun-27.jpg

1.

Phase one begins by quickly evaporating surface water from the washing process. If you have sun, use it. If possible, time your fermentation and washing to see your drying phase begin close to midday to make this as easy and quick as possible. Don’t time your fermentation and washing such that drying begins during the night.

2.

Once surface moisture is gone, move the coffee into the shade and begin phase two. Spread the parchment out thin, as a bed only a single grain deep. You are aiming to dry down to 20% across within a week. Choose airflow (not heat) to speed up the process if necessary. Remember to gently rake the coffee during the day at regular intervals. Modulate the shade and airflow to keep the bed temperature below 40°C. If cold at night, pile parchment up and cover.

3.

Once you’ve reached 20% humidity, phase three begins. You are going to slow drying down, aiming for 10.5% to 12% final humidity across the next 3 weeks. If you are in a very humid region/season dry closer to 10.5%. If you are in a very dry region/season, aim for a final humidity closer to 12%. Increase the bed depth steadily across the 3 weeks, and lower the environment temperature further is necessary. Once the humidity of the coffee has reached your target humidity, the drying phases are complete and it is time to store the parchment.