The world of coffee is a complex and fascinating one. To help you get started in a voyage of discovery, here is a brief introduction.
What we know as coffee, in botanical terms, will be one of over 120 species that form the Coffea genus. The most common of these species in the coffee-drinking world are Coffea arabica and Coffea canephora – which is the species name for Robusta coffee.
Arabica coffee was the first species described botanically, and spread throughout the world for its seeds. Originally grown in Ethiopia (see The Coffee Story) Arabica coffee comprises about 70% of the world’s coffee production. It generally requires higher altitudes (600mts+) and an equatorial climate. The term High-Grown coffee is an indicator of quality, and is therefore difficult to grow and harvest, requiring much manual labour and thus commands high price.
Robusta coffeeis more frequently grown at lower altitudes and on flatter terrain allowing for mechanical harvesting, and can be grown in environments where Arabica cannot survive. The Robusta bean has a higher caffeine content than Arabica, and is often used a component in coffee blends. Vietnam is the world’s largest producer of Robusta.
Within each species of coffee, there are a number of varieties, which are described as having a distinct appearance from other varieties, but will hybridize freely with those other varieties. Cultivars are cultivated variants of a species derived through human influence. These could be selected from existing cultivated stock or from wild populations.
In terms of varieties, there are too many to mention them all here! They are chosen for their resilience to rain or insects, and how they respond to the soil and the coffee processes to be used to produce the ‘green’ coffee beans.
Some of the most common variants are
Typica – this is a tall cultivar of Arabica brought to Java from Yemen in the early 1700’s.
Bourbon – a common cultivar that developed on the Île Bourbon in the Indian Ocean, now known as Réunion.
Caturra – a dwarf variety of Bourbon, developed in Brazil.
Once the coffee ‘cherries’ have been harvested at the farm, there are three main methods of processing coffee, to produce the ‘green’ beans ready for roasting: