Process of Coffee Beans – Before knowing how coffee is processed, it helps if we first know the various structures and layers of the coffee fruit/cherry. Basically, the structure of the coffee fruit (coffee cherry) consists of the pericarp (the outermost skin) and the coffee bean. The pericarp itself consists of several layers such as skin, skin flesh, sap layer (which usually consists of natural sugar and some kind of alcohol content) and parchment. The pericarp layer is the most frequently cleaned, but it is also responsible for adding flavor to the coffee.
After harvesting, the picked coffee cherries are then taken to a processing/milling site to separate the beans from the skin. These seeds will then be dried to keep them safe before being sold to the market. Ideally, coffee has a natural humidity level of around 60%, but it is dried until the humidity is only around 11-12%. The goal is that the coffee beans are not too moist and rotten while “waiting” for sale.
Before continuing to read, take a look at the following video, more about the coffee process chat.
Once picked, coffee cherries will be processed immediately. The processing process also varies. Some of them are as follows.
This natural process is also known as the dry process. This process is one of the oldest techniques in the history of coffee processing. After harvesting, the coffee cherries are spread out on plastic mats and dried in the sun. Some coffee producers sometimes dry it on brick terraces or on special drying tables that have an airflow at the bottom. When dried in the sun, these coffee beans must be turned periodically so that the coffee beans dry evenly, and to avoid mold/rotting.
In the natural process, the dried coffee cherries are still in the form of a fruit/cherry, complete with all the layers. This natural and natural process will make the cherries ferment naturally because the outer skin of the cherry will peel off by itself.
General flavor profile: This natural process is thought to give coffee a fruity note, with general hints like blueberry, strawberry or tropical fruit. Coffee also tends to have low acidity, exotic flavors and more body.
Or also known as the wet process. Generally, this process aims to remove all the skins attached to the coffee beans before drying. After harvesting, coffee cherries are usually ‘selected’ first by soaking them in water. Cherries that float will be discarded, while those that sink will be left for further processing because such cherries are considered ripe.
Furthermore, the outer skin and skin of the coffee cherry will be removed using a special machine called a depulper (peeler). The coffee beans that have been separated from the skin are then cleaned again by putting them in a special vessel filled with water so that the remnants of the skin that are still attached can be completely removed due to the fermentation process.
The duration, or the length of time this coffee is fermented, varies by manufacturer. However, it generally takes between 24-36 hours depending on the temperature, the thickness of the sap layer on the coffee cherry, and the concentration of the enzyme. The warmer the surrounding temperature, the faster the process will be.
General taste profile: Coffees from the washed process generally have a cleaner, lighter character, slightly fruity taste, the body tends to be light and soft with more acidity.
Pulped natural process
This process is often used in Brazil. After harvesting, the coffee cherries are peeled using a mechanical machine to remove the skin and most of the pulp. From here, the coffee beans are then dried on drying tables. The remnants of the fruit flesh that is still sticky will usually fall off in this process. (It is said that the remnants of the fruit flesh that was also dried in the sun added sweetness and body to the coffee).
Honey (Miel) process
This process is somewhat similar to pulped natural and is commonly used in many Central American countries such as Costa Rica and El Salvador. Recently this process has also become increasingly popular in Indonesia. In the honey process, the coffee cherries are mechanically peeled, but this method uses less water than the pulped natural process. The depulper machine will be controlled to determine how much pulp will remain attached to the seeds before drying. This remaining flesh skin in Spanish is termed miel which means honey (honey). Simply put, in the honey process there is a little mucus—or mucilage in English—that looks sticky on the coffee beans. From here this process is then called the honey process. So it’s not because of using honey, huh.
This process is very common in Indonesia and is often referred to as ‘wet milling’. The semi-washed process involves two drying processes. After picking, the outer skin of the coffee cherries is peeled off using a depulper and dried briefly. In general, the humidity of the coffee is left up to 11-12% during the drying process, then in the semi-washed process, the humidity of the coffee is left up to 30-35% before being peeled again until it turns into a green bean. Well, this green bean is then dried again until it is really dry enough to be stored.
General taste profile: Semi-washed coffees tend to have an intense sweetness, fuller body, and lower acidity than washed-processed coffees. Plus, it is said that coffee with this process also has more diverse flavors.
These are the various coffee processing processes that are commonly used and known in the coffee industry. If asked “which process is better?” Of course it cannot be answered because each process certainly provides its own advantages, character and taste profile.