The plant of coffee grows, green and luxuriant, in the tropical zones, where it rains abundantly all over the year and the average temperature varies from 18 to 24°C. It’s an evergreen shrub member of the Rubiaceae family.
There are many different species, but the most grown and commercialized ones are the Coffea Arabica and the Coffea Canephora, known as Robusta coffee. Every species bear fruits with different qualities. More than two thirds of the world production of coffee are of Arabica quality. These beans are flatter and have a S-shape cut. The coffee obtained from them is very aromatic and with a low caffeine content. Robusta coffee, instead, is a very resistant plant which produces a kind of coffee with a more neutral and full-bodied taste. Its beans are rounder and have a straight cut.
Every plant needs roughly three years to bear its first fruits, similar to cherries. Every plant, when well grown, produces up to 6kg of berries per year, equal to more or less 2kg of beans. The fruits need about 6 months to pass from the initial unripe green to the characteristic dark red.
When the fruits ripe, there are two possible harvest methods. The picking consists in the manual selection of the ripe fruits, bean by bean. It’s the most expensive method, which, nevertheless, ensures a crop of premium quality and uniformity. On the contrary, through the stripping method the fruits are pulled out from the sticks manually or with the help of machines. In this way the harvest stage is faster and cheaper, but the fruits won't always have the same ripening.
The bean with which the beverage is made is extracted from the harvested fruits. Beans can be extracted with two different methods, that affect quality in different ways. The dry process is the most common and used one, above all in the areas with an arid climate. Fruits are cleaned and dried in the sun for 2-3 weeks. The seed is peeled mechanically, in order to remove the hull and the pulp, and then passed through a sieve. The coffee obtained in this way is commonly called natural coffee and is characterised by a high sugar content. The second method, called wet process, is longer and more expensive but allows to obtain a coffee with a richer and more uniform aroma. Once the pulp and the hull have been removed thanks to some rolls, the beans ferment with water to eliminate the remainder of the pulp and are dried before removing the parchment. Finally, they are passed through a sieve. This coffee is called “washed coffee” and is blue-green or only green, depending on whether the variety is Arabica or Robusta.