On the branches of the plant, after every heavy shower, white flowers with an intense fragrance and a very short flowering appears: in a few months they will give our coffee beans.
Coffee beans are the seeds in the fruit of an evergreen plant of the genus Coffea in the Rubiaceae family. Many species exist, but the most popular on the market are two: Arabica and Canephora (better known as Robusta).
Cultivation of these plants requires special conditions, and that is why they are grown only along the equatorial belt.
Arabica is the most popular and is prized for its taste and aroma. It is more sensitive to heat, humidity and disease. For this reason, Arabica is cultivated at high altitudes between 900 and 2000 m.
Robusta is considered to be of lower quality, but is more resistant to vermin and adaptable to weather conditions. It is cultivated at lower altitudes, between 300 and 600 m.
Coffee plants need a soil rich in nitrogen, potassium and humus.
Particular attention must also be paid to the inclination of the terrain, exposure to sunlight and orientation to the wind.
On the secondary twigs of the bush, after each downpour, there are short-lived white flowers with an intense scent. The flowers of the Arabica variety are autogams (they are self-pollinated), while Robusta flowers are pollinated by insects attracted by the strong aroma. After about 7-9 months, the flower gives us the drupe (flesh surrounding a pit) resembling a cherry.
Within the fruit are two seeds with a convex side facing each other, and one plate with a small groove. The seed of the Arabica, with low caffeine content, is stretched, with the gap slightly S-shaped, and is more-or-less green in color with shades of blue.
The Robusta seed contains a higher degree of caffeine, is more rounded with the furrow almost straight, and is pale green with gray accents. The seeds are covered by a silvery-white clinging film, and on top of this, a thicker film called the parchment.
When Growing coffee cherries, the different stages of growth development, on the same tree complicates the harvesting procedure. Two systems have been developed.
“The Picking” and “The Stripping”.
The Picking – Is to remove the cherries one by one from each tree, to ensure that only mature cherries are removed, as this prevents damage to the plant and flowers on the plant, simultaneously present. This manual way of harvesting is time consuming and expensive but ensures that the quality of our green coffee is always at its highest standard.
The Stripping consists to remove all the cherries from the tree, regardless of its maturity. Then separate the ripe ones from the rest. This is not always done efficiently. This method can also be done manually or mechanically through the use of special machines that tear or beat all the berries from the branches. This Method is often harmful to the health of the plant. The method of harvesting used is an important point when analysing the quality of coffee.
This clearly affects the final product: an unripe bean gives an astringent taste, bitter and with evident herbal notes by reducing the possibility taste in the coffee fresh and fruity notes. A over-ripe bean may completely disqualify the flavour.
Once harvested, the coffee beans must be processed to separate the beans from the cherries (outer pulp).
Even in this case two different methods can be used:
The dry method, which gives rise to natural coffee.
The wet method, which gives rise to washed coffee.
Green coffee can be subjected to further selection at depots. The selection can be done manually or electronically by reading the color to discard ripe, over-ripe or fermented beans.
The classification of green coffee is done according to certain parameters:
origins; number of defects or impurities; botanical species; processing methods; the year of harvest; the sieve (size and shape of the bean); colour; organoleptic characteristics (especially in Brazilian coffee).
Once selected and classified the product is stored so as to ensure proper preservation. Usually on put them in jute sacks and stored at a certain temperature with relatively low humidity.
Before being shipped to the major ports of destination, the green coffee is transferred to new bags from approx. 60 kg and transported in well-ventilated containers with drainage systems and humidity removal.