The coffee beans have to be deprived of the pulp and separated from the impurities. This happens through two alternative methods: the dry or humid method.

During the dry process the fruits are dried under the sun or in the drier. They are sieved and winnowed, the pulp is taken off and then they are sieved again. This allows the separation of the beans from the impurities. 
The humid procedure is more expensive, but produces the so called "lavados" or "washed" coffees, which are more prestigious than the "corrientes" or "natural" coffees produced with the dry process.
It consists in using flowing channels where the fruits are dragged and sieved so that the shell may be removed. 
Afterwards they are put in fermentation stacks. Here repeated washings take the sugary coating off.
These beans are then dried under the sun or artificially, and are freed of any last remains