Inside a coffee cherry, layer by layer.

The fruit around the seeds

A coffee cherry usually contains two seeds, lying with their flat sides together. Those seeds are the coffee beans. Sometimes only one, rounder seed develops. This is called a peaberry, and published estimates of how often it happens range from about 5% to 15% of cherries.

Reading the diagram from the outside in: the skin is the outer layer, red when ripe in most varieties. Under it is the pulp, sweet and fleshy. Next is the mucilage, a sticky layer that processing either rinses off or leaves on. Then the parchment, a papery shell around each seed. Next is the silverskin, a thin film that hugs the bean and comes loose during roasting. At the centre is the bean itself. Sources name and group these layers a little differently, so you may see six layers described, or fewer.

Why the layers matter

Washed processing removes the skin and pulp, then the mucilage, before drying. Natural processing dries the whole cherry. Honey processing removes the skin and pulp but leaves some mucilage on. The layer that stays on during drying is what changes the flavour. The full comparison is in washed, natural and honey.

The parchment protects the seed until the dried coffee is hulled, leaving the green bean. Roasters then roast the green bean, and the silverskin falls away as chaff.

What we do not say about Monte Romo

This guide describes coffee in general. We have not yet confirmed how the cherries of Monte Romo are processed, so we do not claim a method.