The vast majority of coffee beans used for consumption are produced by two species of shrub of the genus Coffea, namely the Coffea arabica (Arabica) and the Coffea canephora, and within the latter the Coffea robusta variant (Robusta). It is worth mentioning one more species here, the Coffea liberica, which is marketed in a small quantity. In 2014 nearly 60% of the world's coffee production consisted of Arabica, while the remaining 40% was represented by the Robusta coffee.
The world’s coffee production
Coffea arabica is a shrub that can grow up to 10m tall. It prefers the tropical climate zone and an altitude between 600 and 2000m. Its seed has a mild, aromatic, and acidic flavour with low caffeine content.
The plant cultivated today nearly all over the world was originally native to Ethiopia. Several legends and myths are connected to the “discovery” of coffee that dates as far back as the Old Testament times. In the beginning, it was apparently eaten as food for its stimulating effect – the fruit of the coffee plant was simply chewed or eaten ground – and its consumption as a drink evolved only later.
The early spread of coffee was connected to the religion of Islam. The shrubs coming presumably from the Kaffa Province were taken to Arabia, Persia, Egypt, and Turkey in the fifteenth and sixteenth centuries. After the Islamic world, the coffee also conquered Europe, where it rivalled gold in value. By the mid-seventeenth century it had become one of the most important export goods of Arabia, and therefore it was forbidden to be taken abroad under pain of death. In spite of this, Dutch merchants succeeded in obtaining some shrubs, and founded their first plantations in Ceylon and Java. In the New World, French, Dutch, and Spanish colonizers contributed to its spread in the eighteenth century. By the middle of the nineteenth century coffee cultivation had practically spread in the whole world.
There are countless varieties of the Coffea arabica species that developed either naturally or as a result of plant breeding and crossing. Most of them derive from the two Arabica variants, called Typica (Coffea arabica var. Typica) and Bourbon (Coffea arabica var. Bourbon). The rating of varieties is based fundamentally on their resistance to diseases and their yield performance, but the taste quality of the coffee beans and their historical backgrounds are also taken into account.
One example for this is the type Gesha originating near Gesha town, in Ethiopia. After some unsuccessful attempts at cultivation, this type was almost completely "forgotten." Then in 2004 the Gesha varietal from a small farm in Panama won the Cup of Excellence competition in Panama, as a result of which its growing was re-started.
Coffea robusta is the most common variant of the Coffea canephora species, which are often identified with each other, because this variant constitutes 95% of the species. It is similar to the Coffea arabica in appearance, but it grows at lower elevations, below 800 m, within the tropical climate zone. Its seed is heavier bodied and bitterer, and has higher caffeine content. It produces a thicker crema when brewed.
History / Spread
The Robusta was discovered in the area of Congo in 1898. Its distribution began a few years after its discovery, as it showed high resistance against infections and pests that endangered the Arabica shrubs. Its success was due to its strong growth, heavy yield of fruit, and partly to that its habitat was different from that of Arabica. It is grown in greater quantities in the western half of Africa and Southeast Asia.
It is often added to blends because it has a heavier-bodied taste, it produces good crema, and has a low price. Coffee is only rarely made exclusively of Robusta. The Kopi Luwak, which counts as a luxury product, is one of the few exceptions.