Industrial processing must begin immediately after the fruit is harvested, to prevent the pulp from fermenting and deteriorating. The coffee beans can be prepared for roasting in one of two ways.

The oldest, simplest, and cheapest, is the dry method. This produces so-called 'Natural' coffees and is adopted mostly in Brazil and Western Africa. Firstly, the harvested cherries are usually sorted and cleaned to separate the unripe, overripe and damaged cherries and to remove dirt, soil, twigs and leaves. This can be done by winnowing, which is commonly done by hand, using a large sieve. Any unwanted cherries or other material not winnowed away can be picked out from the top of the sieve. The ripe cherries can also be separated by flotation in washing channels close to the drying areas.

The harvested cherries are then spread out, in the sun, on large concrete or brick patios or on matting raised to waist height on trestles. They are raked to avoid fermentation and to expose them evenly to the sun's rays. If it rains or the temperature falls considerable, the cherries have to be covered for protection. Alternatively, after two or three days, coffee can be put in drying rooms, where it is dried by the heat of a burner at 45-60 degrees C. It can take up to four weeks for moisture content of each cherry will have fallen to the optimum 12 percent of their original amount. The outer shell will have become dark brown and brittle. The cherries are then stored in large silos where they are able to continue to lose moisture.

The drying operation is the most important stage of the process, since it affects the final quality of the green coffee. A coffee that has been overdried will become brittle and produce too many broken beans during hulling (broken beans are considered to be defective beans). Coffee that has not been dried sufficiently will be too moist and prone to rapid deterioration caused by the attack of fungi and bacteria.

The other method of preparation is the wet method. It produces so-called 'Washed' or 'Mild' coffees and is adopted in Central America, Mexico, Colombia, Kenya and Tanzania. This involves more capital outlay and more care than the dry method. It does, however, help to preserve the intrinsic qualities of the bean better, producing a green coffee which is homogeneous and has few defective beans. Hence, the coffee produced by this method is usually regarded as being of better quality and commands higher prices. The main difference between the wet and dry methods is that the wet method removes the pulp from the bean within 12-24 hours of harvesting instead of allowing the cherries to air dry.

The beans are separated from the skin and pulp by using a pulping machine which squeezes the cherries between fixed and moving surfaces. The flesh and the skin of the fruit are left on one side and the beans, enclosed in their parchment covering, on the other. The clearance between the surfaces is adjusted to avoid damage to the beans.

The lighter, immature beans are then separated from the heavier, mature beans through specially designed washing channels or by shaking the beans through a strainer into a tank of water. The beans are then stored in fermentation tanks for up to two days during which time the slimy layer of the cherry is separated from its parchment like covering by natural enzymes. The length of the fermentation process is based on the condition of the beans and the climate's condition. When the altitude is low, the fermentation time is short. At higher altitudes, the fermentation can take up to 48 hours.

The coffee is then washed in huge quantities of water (about 100 litres for 10 kilos of coffee). It must then be dried so that it retains only about 10 percent moisture. This can be done by the sun or by mechanical means in artificial driers. After seven to fifteen days the beans are known as parchment coffee and ideally remain in this form until immediately before export.

The outer coverings of the bean (dried coverings of the original cherries in dry process, hull and dried parchment layer in wet process) are then removed. This process is known as hulling and is usually done just before the coffee beans are sold for exporting .

Polishing of beans is an optional process. The polishing process is used to remove the outer-filament and any of the parchment like husk that remains on the bean after hulling. While polished beans are considered superior to unpolished ones, in reality there is little difference between the two.

Although coffee beans are of fairly uniform size and proportion they are graded first by size and then by density. (The elephant bean is the only exception). Beans are sized into different grades by running the beans through sieves and screens with specifically-sized holes. They are then sorted by using an air-jet to separate heavy and light beans. Over-fermented or unhulled beans are now removed. This is usually done by hand as the beans move along a conveyor-belt - it is accomplished with amazing speed and skill. It can, however, also be done by electronic sorting - the advantage of this is that electronic machines can remove beans known as 'stinkers' which are defective but cannot be distinguished by eye. Any flawed or discoloured beans are removed before bagging into sacks marked with grade, plantation and country of origin.

The beans are then ready to be exported.