In this blog I am going to dive into the two main ways coffee beans are processed and what that process entails. If you have been around the specialty coffee world for any amount of time, you have probably heard the words “washed process” or “natural process” thrown around or saw it written on a bag of coffee that you purchased from a local roaster. ( A little coffee buying tip, If the coffee you buy doesn’t have either of those phrases on the bag, or your roaster doesn’t know the difference between the two, chances are you are not getting a high quality bean and it’s not being roasted to its full potential.) Anyway, now that we are done with a touch of coffee snobbery here we go….
Natural process is the oldest method of handling green coffee. Because it doesn’t take a lot of water or special equipment, it is still the preferred method in a lot of African countries. It starts when the farmer determines that the coffee cherry is ripe, which is usually when the cherry is a bright vibrant red, or in some varieties, a honey colored yellow. Then it is picked by hand and taken directly from the field to raised mesh beds, where it is left to dry in the sun. It may take several weeks for this coffee to fully dry down to somewhere between 10 and 12.5% moisture. Because the coffee bean is left inside the cherry as it dries, it has to be treated very carefully and turned often- usually by hand- to prevent the bean from fermenting from the mucilage around the bean. The reason why naturally processed coffees tend to have a deep winey, fruity flavor profile is because as the bean dries, it is given the flavor from the fruit of the cherry drying and slightly fermenting around the bean. If the coffee is not turned often or the sun doesn’t shine enough on the fresh cherries, it can over ferment the green coffee bean, resulting in very acidic coffees. After the coffee is dry, it is de-hulled and graded. Sometimes this is done by a machine, but more often with specialty coffee, it is graded by hand, based on color and bean size. Coffees processed this way shine as an espresso because they produce more of that golden crema on top of a shot. It also makes for a syrupy, winey mouth feel when brewed as a pour over.
Washed process is a newer method of processing coffee, and is an easier and faster way of getting coffee from the field to prepared for shipping. With this process, the ripe cherry is taken from the field and run through a de-pulper machine, which removes the outer part of the cherry. Then the coffee bean is put into fermentation tanks with water. The combination of the freshly picked coffee and the layers of mucilage around the bean, combined with the water, makes a fermenting mass that loosens up the layers still stuck to the bean. This process usually takes anywhere from 24 to 48 hours. Then the coffee is washed with clean water to remove any last pieces of the mucilage and is laid out on beds to dry. Some big commercial farms in South and Central America have drying machines that tumble the freshly washed coffee so it dries even faster. Because the bean has all the layers of the fresh coffee cherry removed before it starts drying, there is no added flavor to the coffee while it is drying. This results in a very clean, bright cup that is higher in acidity. Some coffee purists believe that coffee processed this way is the only way to tell a great coffee bean from an average tasting coffee bean because all the flavor comes while the coffee is growing and attached to the plant.
I hope this explanation helps you understand what you are purchasing and decide which flavor profile you enjoy more. If you are interested in really tasting the difference between the two different processes, try out our Nicaragua for a great natural and our Ethiopia for a great washed. You will be able taste to difference in a winey syrupy mouth feel versus a clean, bright-tasting coffee. Happy drinking