Coffee cherry structure

A coffee cherry consists of 4 main layers: the bean itself, covered with a silver skin (the skin is called silverskin), a parchment shell, or parchment, covered with gluten (mucilage), and the pulp. Let’s talk about each of these layers.
The pulp is what gives the berry its red or yellow color, and what cascara is made from. The pulp is most easily compared to the edible part of a cherry.
Gluten is a sticky, jelly-like, colorless substance that covers the pachment. Gluten is extremely rich in sugars and is indeed sticky to the touch. Gluten is often confused with pulp. The varying amounts of gluten that remain on the pachment during drying after pulping have allowed Central American producers to distinguish several types of haní processing – yellow haní, red haní, etc. The amount of gluten, its texture, and sugar content vary from variety to variety.
Parchment, or parchment shell, is a hard shell in which the coffee bean is located. Parchment serves as an excellent natural protection for the grain and protects it from changes in humidity in the environment, which are dangerous for the processed grain. Hulling (hulling, peeling) of parchment is almost always carried out immediately before export. Parchment is often called not only the shell itself, but also the grain that is in the parchment shell.
Silver skin is a fragile film that covers the coffee bean. It is this that turns into a husk during roasting. Usually, there is more silver skin in coffee processed by hani than in washed coffee. There is a simple explanation for this. The increase in temperature due to the heat released by bacteria during fermentation in washed processing contributes to the destruction of the silver skin, and it lags behind the grain in greater quantities along with the pulp during hulling.
A coffee berry usually contains two beans. If there is only one bean, it is called a piberry.