Last week we touched on coffee picking, the parts of coffee as well as processing methods. If you’d like to check that out click here. I like to keep the posts shorter in length so instead of diving into coffee processing methods in that post, we’re going to get into it this week.
The three methods used worldwide are:
The washed method. (or wet)
The dried method. (or natural)
The pulped natural method. (or semi-dried)
After picking and selecting the ripest cherries, the producers need to be in full control of their cherry-to-green-bean process, whether it is fully washed, dried natural or semi-dry. The moisture content of the ripe fruit generally does not exceed 65 percent. The key is to extract the beans from the cherry and to dry the fruit to a maximum water content of 12 percent, which allows the preservation of the bean.
At least 50 percent of all coffee in the world is processed wet, and for most specialty coffee producing countries this is the preferred processing style. During the wet process, the pulp, including the pulp and the parchment are mechanically removed with a coffee pulper. The remaining mucilage, which sticks to the parchment, must also be removed before drying. This can be accomplished in two ways: by fermenting the parchment beans (dry or in water) or by removing the mucilage mechanically.
Washed coffee is generally cleaner and more consistent flavor.
The sun-dried process is generally used in areas with little or no access to water and countries like Brazil and Ethiopia rely heavily on this processing style. Often, the sun-dried process is used in combination with non-selective picking methods or in countries (like Brazil) where coffee cherries are harvested mechanically. In this processing style the entire cherry is dried, sometimes on elevated “African beds” in the sun and often on the open soil. Once sufficiently dried, the entire hull is removed mechanically to reveal the green beans.
Dried coffees generally has a heavier body and is more complex.
Pulped Natural Method.
The semi-dry process, involves fewer steps. The cherry is pulped with a slightly different pulper as in the wet process. Instead of removing the mucilage after pulping, it is dried together with the parchment. During the final step, the dry parchment is hulled and graded. Specialty semi- dried coffee can be found in Brazil, Ethiopia, Sumatra and Costa Rica. Currently, producers around the world are experimenting with this process, specifically because of the benefits it offers for the espresso preparation method (less acidity, more body and more sweetness).
Semi-dry coffees generally produce a very natural flavor ranging from extremely sweet and fruity, to harsh and pungent.