GROWING AND HARVESTING
A guide to your coffee beans – where they come from and what sort they are.
Coffee beans are actually the seed inside the fruit of the coffee plant, a woody, flowering, perennial shrub or native tree. Coffee is grown in equatorial regions of the world, between the Tropics of Cancer and Capricorn. There are many different models of coffee production, ranging from family small-holdings with one or two trees to large estates with thousands of trees.
Understanding coffee growing and harvesting improves your coffee!
Well known coffee growing countries include:
- Brazil, the world’s largest coffee producer
- Ethiopia, from where the coffee plant is believed to originate
- Kenya, known for producing exceptionally complex coffees
- Sumatra, full of body and earthiness
- Colombia, producing balanced and elegant coffees
- Guatemala, Papua New Guinea, India, Vietnam – the list goes on.
Just like wine, coffee beans grown in different regions have specific flavours and characteristics associated with their origin. It is a combination of historical traditions in coffee cultivation and processing, plant variety and the environmental aspects: altitude, soil, and weather that give each coffee its unique personality and character.
Species and Variety
There are two kinds of coffee bean trees: Arabica (Coffea Arabica) and Robusta (Coffea Canephora).
Robusta trees have a high yield, are pest resistant and grow well in warm, low altitude environments. Arabica trees are very fragile. They are highly susceptible to disease, require a high altitude and cool climate, and yield less per harvest.
In the cup, Robusta beans produce more body and more crema than Arabica beans, however, Robusta often has a coarse and crude flavour. Robusta is primarily used to produce instant coffee or low grade whole bean blends. A proportion of high-grade Robusta is used in traditional Italian blends.
Arabica coffee beans are generally considered finer. Most speciality roasters only roast Arabica, including us. Within the species Coffea Arabica, there are many varieties of coffee tree. This can be likened to the different varieties of red wine grapes (Pinot Noir, Cabernet, Shiraz etc.).
Each variety has its own flavour characteristics and preferred environmental conditions. Well known varieties of Arabica include SL28, Blue Mountain, Bourbon, Typica, Ethiopia Heirloom, Columbian, Gesha, Cattura.
Beans are harvested once per year, usually over a two to three month ‘harvest period’. About 12-20 kg of export ready coffee will be produced from every 100 kg of coffee cherries harvested. Various harvesting methods are used.
Four harvesting methods: (Taken from the “Coffee Harvest” by Michael Clark, et al., 1999)
- Stripping method – This is done by hand removing all the cherries including the flowers. It produces poor results because of the mixing of the good cherries with the damaged ones but it is still practiced in some parts of Africa and Brazil.
- Using a comb to brush the trees – This method uses a comb to remove only the ripe cherries from the tree. This is a time-consuming process but could be worth the time invested because the unripe cherries will eventually become ripe increasing the future yield.
- Mechanical harvesting – Either a vibrator fixed to the trunk of the tree shakes the ripe cherries loose, or rotating brushes attached to the side of the tractor. However, this process damages the tree by ripping off the green cherries, flowers and leaves at the same time.
- Hand picking – This is the most expensive method because hand picking the cherries when they become ripe must be done as many times as required until all cherries are harvested.
The more selective picking methods result in higher quality green beans.
Immediately after picking, the coffee must be processed.