Processing

This refers to how the pulp is removed from the bean.

Dry processing is the oldest method of processing coffee. The cherries are washed and then spread out on drying racks to dry in the sun for several weeks, or alternatively, are dried by machine. During this drying process, the pulp ferments, lending a particular taste to the bean. How the coffee is handled during drying—whether sun-dried coffee is protected against adverse weather or temperature, the machine driers' temperature, etc.—effects the eventual quality and flavor of the bean. After the beans are dried, they are machine processed to remove the dried outer layers.

Wet processed beans have their outer skins removed by machine processing, then the fruit with the exposed pulp is allowed to ferment in tanks where bacteria and naturally occurring enzymes consume the pulp. The beans are then washed and dried, also either by sun or machine, and the dried beans are then milled to remove the remaining layers.

Some beans are semiwashed. The outer skins are removed, but the pulp is allowed to dry on the beans. The beans are then hulled as in the dry process, but the pulp is usually wetted as part of this step.

Broadly put, many feel that dry processing enhances body and complexity, whereas wet processing enhances clarity and acidity. Semiwashed is an attempt to combine these enhancements.