The different processes of drying coffee
Coffee is an exotic product, like cocoa, which can only be grown in certain regions of the world.
Before being a drink, it is a green bean that comes from the fruit of the coffee tree, called cherry.
A cherry usually contains two seeds, but sometimes there are more or fewer.
It is initially green in color, before turning red, orange or yellow (depending on the variety) as it ripens.
Once harvested, coffee cherries must be dried to extract the bean, and the method used has a strong impact on the coffee's flavor profile.
Drying is a process that allows for controlled fermentation to soften the cherry parchment to more easily extract the beans.
The term “coffee processing” actually refers to the drying method used to transform the cherries into green beans, which are then roasted.
There are 3 main processes:
NATURAL (dry)
This is the traditional method, also called “plain coffee” or “natural coffee” because the cherries remain whole.
- Where is it used?
Countries using dry drying.
In countries where the dry season is well defined: Brazil, Ethiopia, Panama, Costa Rica.
- Drying time? Between 10 and 30 days
- What is the principle? The cherries are spread in a layer that should ideally be the thickness of two cherries. This can be on a concrete floor or on raised African beds. They must be turned regularly to ensure uniform fermentation. They are covered at night to protect them from moisture. The moisture content of the cherries, during this process, drops from 70% to 15-30% during drying, then to 10-12%, which is an ideal level for good preservation of the grains.
Floor drying. Source: lafabriqueducafe.fr
Drying on raised African beds. Source: black-coffee.fr
- What are the results on coffee? This will give off intense fruit aromas and the coffee will have body.
WASHED (wet)
This process was developed by Dutch coffee growers in the 17th century on the island of Java. Natural drying was impossible due to high humidity and heavy rainfall. 
The grains are stirred regularly for even fermentation. Source: javry.com
- Where is it used?
Countries using wet drying.
In countries with high humidity: Ethiopia, Kenya, Rwanda, El Salvador, Colombia, Panama.
- Drying time? From 4 to 10 days
- What is the principle?
- What are the results on coffee? Cleaner than natural coffee, but with less body and more pronounced acidity.
HONEY
A so-called “hybrid” method, combining aspects of dry and wet methods.
Also called “pulped natural” outside of Brazil in Central America.
Yellow, red and black honey
There are varying degrees of honey processing depending on the percentage of mucilage left on the parchment grains. The more mucilage left, the darker the color of the parchment when sun-dried. 
The different degrees of honey process depending on the % of mucilage removed.
- Drying time? from 7 to 12 days
- What is the principle? Pulpers separate the ripe cherries from the immature ones. The berries, covered with mucelage attached to the parchment, are then sun-dried on African beds in layers about 2.5 to 5 cm (1 to 2 inches) thick. They are then turned regularly to ensure even drying.
- What are the results on coffee? A rather clean coffee with more body than a washed coffee, but also less acidity. A taste in the cup closer to natural coffees.
TABLE OF ADVANTAGES AND DISADVANTAGES OF THE PROCESSES
Source: book “Coffee is not rocket science”, available from Ma Caféine.
