Everything about coffee processing methods: From dry-processed, natural to washed

Alles über die Art der Kaffeeaufbereitung: Von Getrocknet, Natural bis Washed

The green coffee we enjoy begins its journey as a ripe coffee cherry, harvested either by hand or machine. After the pulp of the coffee cherry is removed, the coffee undergoes various processing methods, some of which utilize fermentation. Globally, there is a wealth of coffee processing methods, which can vary by region. Here, we want to take a look at the three most common methods of coffee processing.

1. Wet Processing

Wet coffee processing is a very water-intensive method of coffee processing. First, unripe or low-quality coffee cherries are sorted out, and then the skin is removed from the coffee cherry. In the next step, the pulp of the cherry is separated from the coffee bean. These steps occur with a very high proportion of water in various washing processes. However, since the typical coffee growing regions – Ethiopia, Kenya, or Tanzania – are usually areas with very little water and rainfall, this processing method is not frequently used.
Only the mucilage layer and the parchment hull remain on the coffee bean. Then the coffee beans are subjected to a fermentation process in large tanks.

kaffeeaufbereitung Nasse Aufbereitung washed

What is Fermentation?

Fermentation is a biological process of anaerobic respiration in which materials ferment with the help of bacteria, fungi, or added enzymes. In the case of coffee beans, bacteria are added externally for the fermentation process. These bacteria free the beans from the sticky parchment skin residues and dissolve small remnants of the pulp.

There are two types of fermentation:
a) In wet fermentation, water is added to the tanks, initiating the fermentation process with microorganisms.
b) In dry fermentation, the moisture of the pulped coffee beans alone is sufficient to initiate the fermentation process.

After fermentation, which lasts between 12 and 36 hours depending on the amount of added microorganisms and the temperature in the fermentation tanks, the coffee beans are washed again. The parchment hull can now be easily detached from the beans. After that, the beans must either air dry on drying patios or be dried in drying machines.

How does coffee from wet-processed coffee beans taste?

If you prepare coffee from wet-processed coffee beans, you will usually taste a very lively flavor and a mild body with a pleasant acidity. The present acidity creates a slight tingling sensation on the sides of the tongue.

2. Dry Processing

In the dry processing of coffee beans, water is only used in the first step. The coffee cherries are washed and thoroughly cleaned. Afterwards, they are laid out on special mats for approx. 2-3 weeks in the hot sun. The bean still has its skin and pulp attached. By turning them several times during the drying period, the pulp and skin easily loosen. At the end of the drying period, the parchment-like hull, the pulp, and the silver skin can be very easily separated from the coffee bean by machine. No fermentation takes place in this process. At the end of the process, the coffee beans are washed and sorted again.

kaffeeaufbereitung Trockene Aufbereitung natural

How does coffee from dry-processed coffee beans taste?

A floral scent and a fruity, slightly floral aroma await you in the cup. A complex body with a sophisticated fragrance characterizes coffee varieties that have been naturally dried.

3. Semi-Dry Processing

The semi-dry processing of coffee beans is also called “pulped natural.” In principle, this method is almost the same as dry processing. However, it is not the whole coffee cherry that is dried, but only the pulped kernel, i.e., the pure coffee bean. No fermentation takes place in this process either.

How does coffee from semi-dry processed coffee beans taste?

The aroma is complex and intense. The flavor is described as umami. Translated, this means savory or hearty. Here, it is not really a taste or a field on the tongue that is responsible for the respective taste sensations. Rather, the body is described here. The feeling or density when you have the coffee on your tongue. Heavy, full, soft, and delicious. That is umami.

Conclusion

The type of coffee processing significantly influences the taste of our beloved coffee. There is a variety of methods by which coffee is processed, and each brings its own charm and influence on the taste. Whether it's the "natural," "pulped natural," or "washed coffee" method, each processing has its own advantages and disadvantages. In dry coffee processing, also called "natural coffee," the coffee cherries are spread out for two to three weeks and dried by the sun. Semi-dry coffee processing follows a similar method, but only the pulped kernel, the pure coffee bean, is dried. This special type of processing gives the coffee an intense umami flavor. In the wet method, often referred to as "washed coffee," the coffee beans are placed in large tanks with water only a few hours after harvest, where the fermentation process begins. This high-quality process, in which the mucilage layer and parchment skin are mechanically removed, leads to a coffee characterized by a lively taste and pleasant acidity. Factors such as fermentation and the separation of the coffee cherry pulp play a central role. It is fascinating to see how coffee processing influences the taste and aroma, from a light espresso to a heavy, full-bodied coffee. One thing is certain: for every coffee lover, there is the perfect, processed coffee that convinces with its special type of coffee processing. It is therefore worthwhile to try different processed coffees and thus discover the best coffee for yourself.

Kaffeeaufbereitung

Frequently Asked Questions (FAQ)

What is meant by "natural" and "pulped natural" in coffee processing?
"Natural" refers to a dry processing method in which coffee cherries are dried in the sun before the pulp and skin are removed. "Pulped natural," on the other hand, means that the coffee cherries are first washed and the pulp is mechanically removed from the coffee bean before they are dried in the sun.

How does the processing method influence the taste of coffee?
Depending on whether the coffee has been dry, semi-dry, or wet processed, the taste varies. For example, wet processing generally leads to a livelier and more acidic coffee, while dry processing produces a more aromatic coffee with fruitier notes.

How quickly should processing take place after harvest?
Ideally, processing should occur within 24 hours of harvest. This helps maintain the freshness and quality of the coffee cherries and significantly determines the taste of the coffee.

What distinguishes wet-processed coffee from dry or semi-dry processed coffees?
In wet-processed coffee, the coffee cherries are first washed, and the beans are placed in large tanks to ferment. In dry and semi-dry processing, the coffee cherries or pulped beans are dried in the sun.

How are the mucilage layer and parchment skin removed during coffee processing?
After turning and drying, the pulp and skin loosen more easily. The remaining mucilage layer and parchment skin are mechanically removed to obtain the pure coffee beans.

What is the significance of "washed processing" for coffee?
In washed processing, also known as "washed coffee," the coffee is thoroughly washed to remove all remaining fruit residues. This often leads to a clean, clear taste in the cup of coffee.

When are coffee beans prepared shortly before export?
Coffee beans are the seeds of the coffee cherry. They are packaged after processing, drying, and sorting, and are then ready for export.