The most renowned coffee bean in the world is the Coffee seed, an evergreen shrub in the family of Rubiaceae. There are over 80 species of Coffea, but only two of them are commercially used with their seeds roasted and grounded to make coffee:Coffea arabica and Coffea canephora, usually known as Arabica and Robusta.
The first Coffea to have been used was the Arabica, which originally came from the highlands of Ethiopia, and is usually cultivated between 1,000 and 2000 m altitude. It is the most highly prized and valuable, and accounts for 75% of world coffee production. The Arabica beans are green or green-blue, with an elongated shape and low caffeine content, but rich in aroma and mild acidity level.
Coffea canephora is known as Robusta, because it is a strong plant that can resist against parasitic infections and withstand harsh climate conditions, like high temperature and heavy rain. It has its origins in central and western subsaharan Africa, where it grows well in a wider range of altitudes, starting from 200 m above sea level. The Robusta beans, which are yellow and brown-yellow in colour and rounder in shape, have higher caffeine content and make a stronger coffee.
Since the early days of its discovery, coffee has always been analyzed to understand its quality and content, but it is only recently that all the substances in the bean have been actually classified. Although the World Health Organization defined it as a "non nutritive dietary component”, you could hardly find a drink richer in active and non active ingredients such as coffee. So far 900 different substances have been identified in a coffee bean, including minerals such as potassium, calcium, magnesium, phosphates and sulfates. 40% of the mineral content of coffee is composed of potassium, which is fully extracted during the preparation of the drink, and found in the cup of coffee we drink. Coffee also contains lipids and waxes that are lost in the filter during the preparation, regardless of the kind of filter employed. But the most important substance, both for concentration and properties, is caffeine.
At room temperature, caffeine is a white, odorless, solid, bitter substance. After caffeine is ingested, it is rapidly and completely absorbed from the stomach and intestines into the bloodstream. It has a stimulating effect on mood and behavior, acting on the chemical synapses in the central nervous system, and a cardiostimulanting effect. Caffeine is also used in pharmaceutical preparations for the treatment of migraine and, given its thermogenic and lipolytic properties, also in cosmetic and skincare products to treat cellulites.
