Processing the beans, or preparing them for roasting, is done in one of two ways: 1) the dry method, or 2) the wet method.

The Dry Method
This is the simplest, cheapest and most traditional method of processing coffee. The harvested cherries are spread over a concrete, brick or matting surface, ideally in sunlight, and raked at regular intervals to prevent fermentation. If it rains or if the temperature falls, the cherries have to be covered for protection.

After about seven to 10 days, when the moisture content of each cherry will have fallen to about 11 percent, the cherries are dry. The outer shell will have become dark brown and brittle, and the beans can be heard rattling around inside their husk.

The dried cherries are then stored in silos, where the beans continue to lose moisture.

The Wet Method
This method requires greater investment and more care than the dry method, but it causes less damage and helps to preserve the intrinsic qualities of the bean. The main difference between the two methods is that the wet method uses a procedure to remove the pulp from the bean within 12-24 hours of harvesting, instead of allowing the cherries to air dry.

Using a pulping machine, the beans are separated from the skin and pulp, which are washed away with water. The lighter, immature beans are separated from the heavier, mature beans through specially designed washing channels or by an Aagaard pre-grader, a system involving shaking the beans through a strainer into a tank of water.

Next, the beans are stored in fermentation tanks for 12 to 48 hours, during which time enzymes work to naturally separate the slimy layer (parenchyma) from the parchment-like covering (endocarp). When the process is compete, the endocarp has a “pebbly” feel. Fermentation is usually carried out in concrete tanks, which vary considerably in size. The length of the fermentation process is based on the condition of the beans and the climate's conditions. In regions of low altitude, fermentation time is short. At higher altitude, fermentation can take up to 48 hours.