How many varieties of coffee are there?

When we talk about coffee varieties we usually think of Arabica, Robusta, and Liberica. In reality there are innumerable types of coffee in the world (more than 100 varieties), but from a commercial point of view there are about ten of the best known varieties.What changes between one variety of coffee and another? The taste certainly changes between one type of coffee and another, making it more or less strong and with a different aroma; the caffeine content which can be higher or lower; adaptability to different climates and terrains. Even the cultivation altitude greatly affects the production of one variety of coffee and another, in fact some types prefer those at high altitudes (such as arabica), others less so.

Some types of coffee are present in nature, in their areas of origin, but it is also true that many others have instead been grown and created artificially. So let's see all the types of coffee currently on the market and what are the main differences between them.
  

The types of coffee compared

Arabica variety

The quality of Arabica coffee is one of the best known and most consumed in the world. It is also the species that was first used to make coffee. It has a lower caffeine content than other species on the market. 
Arabica is native to Ethiopia, Sudan, and northern Kenya, but is now also cultivated in Arabia, Brazil, etc. 
Arabica plants grow mainly in areas at high altitudes (between 1000 and 2000 meters) and in soils that are very rich in minerals.

Robusta variety

The cultivation of the Robusta coffee variety only began in the 1800s. It is one of the best-selling on the market because it is cheaper as it grows easily in areas at altitudes lower than 700 meters.
It is native to tropical Africa but is now cultivated in various countries thanks to the lower cost required for planting and resistance to disease.
Robusta has a higher amount of caffeine than Arabica and has a more bitter and stronger aroma.

Liberian variety

The Liberica variety is a little less common commercially but widely used to obtain new types of coffee by crossbreeding. It is originally from Liberia, but grown today mainly in Indonesia and the Philippines. This plant is very resistant to parasites, and requires a lot of water and high temperatures.
Although the Liberica is qualitatively lower than the others, it is a variety with a very aromatic flavor.

Excelsea variety

It was discovered in 1903 in Africa and is considered very promising in quality as it is very resistant to disease and drought. Excelsea beans provide a very fragrant coffee, similar to Arabica.
Shortly after its discovery, experts called Excelsea a mere variety of Liberica, however it is still considered to be a separate variety today.

Racemosa variety

With the Racemosa we begin the review of the lesser known species of coffee.
Racemosa is a very rare variety of coffee, originally from Mozambique, which grows on wild coasts, river banks and rocky surfaces. Racemosa is one of the few coffee varieties that starts with a very low caffeine content of 0.38% and is therefore classified as caffeine-free.
Racemosa has an aroma that recalls different flavors including mint, licorice, and wood. Despite its bitter taste it is unexpectedly light.

Stenophylla variety

Stenophylla is a variety of coffee that has almost disappeared because it is not commercially viable. The reason is very simple, Stenophylla takes about 9 years to ripen and bear fruit, five years more than Robusta and two more than Arabica. It is native to West Africa and has a coffee with a flavor comparable to tea.

Mauritian variety

Originally from Mauritius, she is considered one of the most promising at the moment. Her taste is strong and bitter but with an extremely intoxicating scent.
In addition to these varieties ranging from the best known to the least known, we find many others including the Dewevrei from the Congo, the Abeokutoe from the Ivory Coast, the Cogencis also from the Congo.