The Plant
A coffee plant can live as long as 60 years and remain productive for 15 - 20 years. They have deep green leaves and can grow as shrubs or trees. They can grow to a height of 10 - 15 meters when fully mature but on plantations are kept at three meters for harvesting purposes.
The Flower
Small white flowers called Coffea flowers grow on the secondary branches of the Coffea shrub in continuous cycles during the year. Coffea flowers are self-pollinating, rich with a pungent odor and wither over the course of days to produce the fruit.
The Fruit
When fully ripe, the fruit of the Coffea shrub is similar to a cherry in terms of its bright red colour, and soft sweet pulp. Each fruit contains two beans which are covered with a silver-coloured membrane, enclosed in a second, tougher skin called parchment and are semi-oval in shape.
The Harvest
Hand picking is the best method of harvest for the Coffea plant. This is because the continuous production of the fruit guarantees that at any given time there are unripened, fully ripened and over ripened fruit on the shrub. Hand picking ensures that nothing gets through that would contaminate the batch and allows the unripened fruit to fully ripen before being pick and the over ripened fruit to be discarded naturally. The other method of harvesting is called stripping in which the shrub is fully stripped of all of its fruit. This method is fast but far less accurate.
Processing
There are two methods of processing still used today.
These two processes are called the dry process and the wet process.
The Dry Process- In this process the cherries, after being separated from all twigs, debris etc, are spread out for a few days on threshing floors in the fresh air. The beans are then removed from the hulls and parchment in a hulling machine in which the hulls and parchment are crushed. This method produces "natural" green or "unwashed" green coffees. When the fruit is harvested via stripping, dry processing is necessary.
The Wet Process- This process is longer and harder and is generally used for handpicked cherries because they are more uniform in size. The fruit are placed into pulping machines which remove the hulls. Then for several days the beans, still in their parchments, are left to ferment or be "washed" in large tanks of water which removed any decomposing pulp that still remains. Then they are sun dried, freed from their parchment with the use of centrifugal force, polished, electronically sorted for defective beans, graded for size, form and colour and are now ready for selection and shipment.
Selection
Coffee goes through a continual series of quality control tests beyond what any other agricultural product goes through. Going above and beyond general detection and elimination of defective beans, these controls serve as a basis for the final selection required for a proper blend.
Shipment
Green beans preserve their unique characteristics longer than roasted beans, thus the beans are shipped unroasted in 60kg (132 lb) jute bags.
Blending
To create different balances in taste, richness and aroma beans of different characteristics and origins are blended together. The greatest blends of taste and aroma are achieved if blending is performed before roasting.
Roasting
Roasting gives coffee its unique aroma, taste and colour. 70% of the final characteristics that make coffee one of the most enjoyable beverages in the world happen during roasting. Through moisture evaporation the coffee beans lose 20% of their weight. The beans are rotated in huge heated cylinders. Due to physio-chemical reactions, while the beans lose 20% of their moisture they expand by 60% at the same time. The physio-chemical reactions are responsible for coffee's flavour and its over 900 volatile aromas because they activate substances inside the cells. The strength and intensity of the final flavour is determined by the final temperature and length of the roast. The temperature can never exceed 230 degrees Celsius and is precisely controlled.
