The harvest and processing process of coffee beans and two basic processing methods

Picking: due to climatic differences, the harvest season is usually from September to March in the Northern Hemisphere and from April to August in the Southern Hemisphere. When the coffee beans are ripe, they can be picked. In many alpine slopes, coffee must be picked manually. In relatively flat producing areas such as Brazil, Australia and Hawaii, they can be picked by machines. Obviously, the cost of manual picking is higher, but the advantage is that it can ensure that the fresh fruits are ripe, avoiding picking other sundries, and because the maturity time of coffee fruit is different, manual can pick the same tree several times, which is also a key step to obtain high-quality coffee. On the other hand, machine picking will pick off the fresh coffee fruit of the whole tree, regardless of whether it is ripe or immature, even with leaves and branches. Relatively speaking, it is relatively rough.

Treatment method-traditional sun processing: this is one of the basic methods for the treatment of coffee fruit, also known as natural drying or non-washing. Especially in Africa and other producing areas where water resources are not rich, almost all of them use tanning. Directly dry the coffee fruit until the whole is dry, and then remove the peel and pulp to get the coffee beans. In the past, coffee farmers used to dry in the open space in their own yard, which was relatively rough and slightly careless, and coffee would be infected with miscellaneous smell, but with the improvement of coffee production technology, people in some producing areas began to use off-the-ground drying, which greatly reversed the image of sun-tanned coffee. Sun-treated coffee is mellow and sweeter. Usually, when the coffee fruit is dried, it is put into a grinder to remove the skin and pulp, and the raw coffee beans with silver skin are directly obtained and sent to the processing plant for further grading and selection.

Treatment method two-water washing treatment method-1 cleaning and separating coffee beans: the picked fresh coffee fruit is washed in a pool to separate the ripe fruit from the immature fruit and overripe fruit floating on the surface.

Washing method-2 remove the peel and pulp: the washed fresh coffee fruit is put into the peeling machine to remove the peel.

Peeled coffee with shell beans.

Washing method-3 fermentation: because the peeled coffee beans are also covered with a layer of insoluble mucous membrane (also known as "pectin") in water, these coffee beans are piled up for the fermentation process, which quickly decomposes the mucous membranes. make it easy to wash off by water. Wet fermentation can be carried out by immersing coffee beans in the fermentation tank, or dry fermentation can be carried out without soaking. The length of fermentation time depends on the fermentation temperature, coffee variety, coffee quantity and fruit ripening degree. In most areas, fermentation takes an average of 12-36 hours.

Washing method-4 washing shell beans: once the fermentation is finished, the washing water must be flowing water, the healthy mature coffee beans will stay at the bottom of the pool, and the defective coffee beans will float on the surface. after the washing process, the coffee endocarp (also known as parchment) still exists.

Washing method-5 drying: washed shell beans need to be dried, usually dried in the open air, and coffee beans need to be turned constantly to prevent unnecessary fermentation. But also can not dry too fast, step by step to dry, otherwise, it will lead to coffee beans rupture and loss of aromatic substances.

Colombia's greenhouse-style shade to prevent the sun from drying too fast.

Sometimes because of the weather or too much work, large coffee processing plants use machines for drying.

Shelling: at this time, the parchment shell is removed by the machine, and the strong air flow in the machine can blow away the impurities and clean the coffee beans again.

Grading: after shelling coffee beans for specific weight, size screening and other grading procedures. Usually, the more these procedures are done, the better the quality of the coffee will be. (from this process, coffee beans treated by sun, water or other methods will go through the same grading process.)

Pick: this is the last procedure for coffee beans before they are packaged and exported. Most coffee beans go through the process of manual selection, and the more carefully the selection is done, the fewer defective beans there will be. Only such a careful selection can ensure the high quality of the final coffee.

A coffee worker in Indonesia is picking coffee beans.

Weighing and packing: weigh the final raw coffee beans and put them in a bag. The packaging specifications of most countries are 60kg/ bags. A few countries use the specification of 70kg/ bag.

Some small estates accept custom production, so the packaging specifications of 30kg/ bags are also used.

Coffee beans packaged and waiting for export.

There are two basic treatments: sun-drying and water-washing. Relatively speaking, the sun-type process is much simpler, so, from the perspective of commercial beans, the price of sun-type coffee beans has been lower than water-washed coffee beans, the status is relatively low, and so on. However, in recent years, some processing plants have been able to produce high-quality suntan coffee beans, such as boutique sun-tanned Yega Chuefei, which has a very high sweetness, rich flower and fruit flavor and mellow thickness, which once subverted the better practice of washing beans. Of course, such exquisite sunbathing is still a minority. On the other hand, the water-washed coffee beans have high acidity, clean taste spectrum and elegant fragrance, and most of the high-quality coffee beans are still mainly washed.