Coffee Bean Processing —— Shelling

Before the coffee beans are exported, the inner peel on the coffee beans is removed by grinding. The process of removing, cleaning the endocarp and drying it is called shelling or peeling.

It is more difficult to remove the inner end of the coffee beans during the wet processing than during the drying process, so different shellers are required to have two main types: friction husking and compacting the sheller.

Engelberg and African model of the friction sheller are suitable for dry or wet coffee beans: in a cylindrical box, the coffee beans are squeezed between the linear ribs and the knife, and the shell is scraped by a knife. Showing the beans. “Parchment coffee beans” are usually shelled on a Smoot friction sheller. Smoot is a Belgian, descendant of the Scots. He was born in Kneissberg, Prussia. He settled in Guatemala in 1844. He developed a coffee bean peeler, which is equipped with a rotating body with a screw, rotating The body rotates in a box with a spiral, while the spiral rotates in the opposite direction. The inner peel is peeled off from the coffee beans as the coffee beans are pushed by the power along the rotating body. Because the rotating body rotates relatively slowly, the rotating body produces less heat than other types of shellers.

Other shellers include rolling shellers and crossbar shellers. Rolling shellers are mainly used for dried coffee beans produced in South America. The inside of the crossbar Coffee sheller machine is equipped with a knife.

Except for Brazil, the friction Coffee sheller machine is not used in other places, but the “parchment coffee beans” are processed by the compacting sheller. The squeeze Coffee sheller machine includes a horizontal plate that rotates inside the ring body, around which the edge of the plate is iron or iron. When the machine is rotated, the coffee beans come into contact with the iron needle due to the centrifugal force, so that the inner peel shell falls off.

Coffee beans must have a moderate moisture content when the coffee beans are peeled, otherwise they may break.