The refining method of coffee beans

Generally speaking, there are three ways to treat the process from coffee fruit to raw coffee beans-dry treatment, washing treatment, semi-dry and semi-wet treatment. What is the difference between the three steps? Which is better or worse?

(drying in the sun field)

Drying treatment is the most primitive and simple treatment.

1. After harvest, the coffee fruit is sent to the sun field to spread evenly, often turned over so that the coffee fruit can be evenly dried, but also to prevent excessive adsorption of the smell of the ground. Use sunlight for natural drying, a process that can last for several weeks (depending on the weather).

two。 After drying in the sun, the red coffee fruit turns black and dry. The next step is to put the sun-dried fruits into the shell removal machine for shelling and peeling, and the coffee beans that are close to coming out of the storage are obtained.

3. Then use machine or manual work to pick out defective beans and evaluate the grade of coffee beans. Before the export, the coffee beans can be polished and other procedures to remove the silver film.

(wash treatment, remove the skin and pulp)

(washing treatment, fermentation tank)

(drying treatment of water washing treatment)

Washing treatment is a more complex way to refine coffee beans.

1. The coffee fruit is actually put into the sink after picking, in order to remove the leaves, rubbish and dead beans floating on the water.

two。 Coffee fruit through the pulp removal machine to remove the exocarp and pulp, as well as pebbles, branches, bad beans and other impurities.

3. The coffee beans that remove the outer skin and flesh are put into the fermentation tank for fermentation to facilitate the removal of the mucous membrane attached to the inner pericarp. The water quality must be clean and the fermentation tank must be treated carefully. Only in this way can impurities and bacteria react with the mucous membrane. Affect the quality of coffee beans (some fancy farms even change the water in the fermentation tank several times at this step to ensure that coffee beans are not affected)

4. Then the coffee beans are put into the sink to wash the coffee beans and separate the light beans and the full and heavy beans. After this treatment, the moisture content of coffee beans is reduced to about 50%, and then the coffee beans are spread out in the sun for drying until the moisture content is reduced to about 12% (some places are dried by dryers).

5. Then the coffee beans go through the shelling machine to remove the residual endocarp, and the treatment work is basically completed. finally, the defective beans are removed and the grade of raw coffee beans is evaluated.

Semi-dry and semi-wet treatment is a kind of coffee bean refining method between the former two. The biggest difference from washing treatment is that it does not go through the fermentation tank. After the coffee beans are harvested, the leaves and other sundries are removed through the storage tank, and the exocarp and pulp are removed by the pulp removal machine, then the coffee beans are placed in the sun field for sun drying, and finally the coffee beans can be dried by machine.

What are the advantages and disadvantages of the three treatment methods?

The drying method does not require repeated steps and expensive equipment, so it is simple and low-cost, because it is naturally dried, so it retains the natural flavor of coffee, and the coffee made from sun-treated beans will have a good performance in terms of mellowness. but the precision is not very good, it is easy to mix a lot of impurities in it. The steps of washing treatment are complicated, using more equipment and manpower, so the cost is higher, but because each step is controlled to reduce the existence of sundries and defective beans, so the overall quality of refined coffee beans is better than that of dried coffee beans, and the taste of the coffee is richer and clearer. The method of semi-dry and semi-wet treatment is between the two, and its quality is better than that of dry treatment but not as good as that of washing treatment.

At present, water washing treatment is becoming more and more popular, because coffee beans are more and more popular with buyers because of their high delicacy. There are not many countries that still use dry treatment, mainly Ethiopia (there is no adequate water source), Brazil (the vast flat terrain is very suitable for dry treatment), but some areas of Brazil and Ethiopia have begun to use water washing treatment.

Generally speaking, although the process of washing treatment is complex and the cost is high, because the refined system of coffee beans is high and the flavor is better, it is respected by the international market, and the price of coffee beans is relatively high, although washing does not necessarily represent high quality.