The most traditional processing method of coffee beans

Drying is used for unwashed coffee beans. Wet treatment is used for thoroughly washed or semi-washed coffee beans. Except for the more common use of drying in Brazil and Ethiopia, most Arabica coffee beans are processed by wet treatment. In Indonesia, some Robart coffee beans are processed by wet treatment, but this is not common there.

Drying is the cheapest, simplest and most traditional method of processing coffee beans. When processing, the harvested fruit should be spread on the cement floor, brick floor or straw mat. Ideally, the fruits should be raked flat in the sun and at regular intervals to prevent fermentation. If it rains or the temperature drops, these fruits must be covered to prevent damage.

After about 4 weeks, the water content of each fruit will drop to about 12%, when the fruit is dry. In Brazil, coffee beans at this stage are given a confusing name: coco. At this time, its skin turns dark brown and fragile, and coffee beans can be heard cackling in the shell.

The process requires more technology than it seems. Because coffee beans can be overdried, if this happens, they can easily be damaged at the next stage, when they are shelled. On the other hand, coffee beans that are not sufficiently dried are also vulnerable. The next step is to store the dried fruit in the cellar for a while. During this period, the water in fresh coffee beans continues to evaporate.