Coffee Processing Methods
The way that coffee cherries are processed determines the outcome of the coffee in your cup.
There are many different coffee processing methods used in the specialty coffee industry. Farmers are constantly increasing their knowledge about, innovating their methods of, and experimenting with processing methods to improve the coffees they produce.
Below, we’ve laid out the three main coffee processing methods, and how these methods affect the coffee you drink.
Dry Process – Natural coffees or Unwashed COFFEES
- The dry process is often referred to as “natural coffee” because of its simplicity, and because during this kind of process the fruit remains intact and undisturbed.
- With this method, the bean dries and naturally ferments in its skin and the mucilage (fruit pulp) of its cherry. This occurs under careful control over a time span of 25-35 days depending on climate.
- Once dry, the pulp and skin are removed from the bean, this is called dry milling.
- Naturals tend to be relatively inconsistent due to a high risk of mold, they also require long-term care and attention to detail. With naturals, each bean has it’s own levels of sugars and alcohols, and these components can also affect the uniformity of the cup.
- When handled correctly, the natural process gives coffee beans a beautiful, fruity, and complex taste.
Wet Process – Washed coffees
- Traditional wet process starts when ripe coffee cherries arrive at the mill.
- The skin of the fruit is stripped off using a machine called a depulper. The remaining mucilage (sugars) are removed through fermentation in a clean tank. This can take anywhere from 12 to 48 hours.
- After fermentation, the beans are washed again to remove any remaining mucilage.
- There are several methods used to dry the coffee beans. They can be laid on a patio, on raised (African) beds, or dried mechanically. An even, dry climate is essential to produce quality washed coffees.
- Washed coffees produce a very clear cup, with a bright acidity and liveliness. A real treat!
Honey Process – Honey coffees
- With the honey process method the skin and pulp are removed, but some or all of the mucilage (sugars) remains. After the pulp is removed, the beans are dried quickly (10-15 days) and must be agitated frequently in order to prevent mold!
- Depending on the amount of mucilage remaining on the bean, honey coffees can produce different levels of coloured parchment during drying. These levels are usually referred to as yellow, red, and black. The darker the colour, the more complex the cup of coffee.
- Honey coffees have some of the body and sweetness of naturals, but they also retain some of the acidity of washed coffees.