Arabica? Robusta?
Have you ever wondered what species of coffee you are drinking? Most people probably heard the words arabica or robusta, but there’s more than 120 unique species of coffee tree with countless varieties and cultivars. Unfortunately, only a few are commercially useful. 98% of the coffee market consists of only two species, the aforementioned coffea arabica with a 60% share of the market, and coffea canephora, colloquially known as robusta, which is an outdated synonym. This one constitutes about 40% of the production. A minority, only about 2% of the coffee market, is made up of coffea liberica and its variety, coffea liberica excelsa.

Robusta
There are important differences between arabica robusta, in some ways, they are almost opposites of each other. Robusta is a truly sturdy plant. It doesn’t need nearly as delicate conditions for its growth as arabica does. It is easier to cultivate, which is possible already from the altitudes of 800 m.a.s.l.. Its name does not come out of nowhere - it has a hardier root system, it is generally bulkier and grows faster, starts giving fruit sooner, yields more, the cherries can grow larger and contains up to double the amount of caffeine of arabica. An easy way to tell it from arabica is by its typically wrinkled leaves.

There is a longstanding belief that the taste profile of robusta is nowhere near as rich as the one of arabica, and that’s why it has long been considered something lesser, uninteresting and has been destined for a life of commodity coffee. The taste expectations in robusta are usually focused on earthy, alkaline tastes distantly reminiscent of nuts or chocolate. But in properly cultivated and processed robusta, one might find a far richer spectrum of tastes, such as aromatic woods like cedar or sandalwood and spices such as cinnamon or clove. The defining characteristic of robusta are its exclusive alkaline flavours, for example black tea, cotton, dried tobacco or fresh tobacco leaves. Robusta can reach high sweetness levels and remind of ripe bananas, papaya or other fibrous fruits. And in special cases, the alkaline taste makes space for an acidic taste, which bring the taste of the coffee close to arabica.

Working with robusta, one might notice it is a very stable coffee boasting a thick crema, the characteristic foam topping a cup of espresso. It is these properties, such as stability, higher caffeine content, rich crema and lower price, which made robusta a traditional part of Italian espresso blends, where it complements the taste qualities of arabica. According to the original recipe, ristretto is even prepared out of 100% robusta.

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Arabica
On the other hand, arabica exhibits vastly different properties. Already the lower content of caffeine leads to a big difference, as it has a bitter taste of its own. The specific of arabica, compared to alkalinity or robusta, is the fabled acidity. The diversity of tastes to be found in arabica is truly vast. One might find all kinds of fruits, from blackcurrants we know from our backyards to pineapples, mangoes or lychees that come from (in our point of view) exotic lands. Common are tastes of nuts and seeds, various floral and herbal tones and all kinds of tea flavours. It is not uncommon to discover tastes of cereals or dairy. Light-roasted coffees often exhibit tones of all kinds of vegetables, which is a current trend in Nordic countries.

The price for such diversity of tastes is a weaker root system, which leads to generally slower growth and smaller yields. The trees are less sturdy and thus more susceptible to weather conditions, diseases and parasites. It has much more specific requirements for the soil and temperatures and that’s also why it has to be grown higher, from 1200 up to 3000 m.a.s.l., where precipitation is more abundant and nutrients in the soil more concentrated.

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Comparison of arabica and robusta
If you had a chance to compare arabica and robusta side by side, you should be able to tell them apart easily. Robusta is usually rounder, compared to the elongated shape of arabica, and the line running through the middle of the bean is pretty much straight. In arabica, this line produces a characteristic wave. But, just like pretty much every rule, this one has countless exceptions, thanks to the diversity of the cultivated varieties.

The world of specialty coffee, founded upon transparent origin and of course bean quality, has been built around arabica. These days though, one might notice robusta coffees slowly trying to gain a foothold in this market as well, thanks to improving approach to robusta both in cultivation and processing, but also marketing. This allows robusta to realize its potential and offer a cup taste experience just as unique and interesting as arabica.

Robusta comes from western and central Africa. Uganda has proclaimed itself the “homeland of robusta”, but the truth is that it shares this status with many surrounding countries. The biggest plantations can be found not only in its traditional homeland in western and central Africa, but also in India, Vietnam, Indonesia or Brazil.

Arabica most probably comes from the rainforests in lands now belonging to South Sudan and southwestern Ethiopia, whence it quickly spread around the Horn of Africa and to Yemen after its discovery. Arabica coffee tree thrive not only in Eastern Africa, but also throughout Yemen, India, Southeast Asia all the way to Papua and Northern Australia and many Oceanic archipelagos all the way to Hawaii. On the other side of the world, pretty much the entire Latin America cultivates arabica coffee.

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Other species
Liberica and its variety excelsa, mentioned at the beginning, only constitute and tiny part of the world’s production. But they are so unique that they definitely deserve a mention. Although excelsa has recently been reclassified as a variety of liberica, they are gastronomically so different that they are considered two different coffees.

Liberica grows wildly in equatorial Africa from Liberia all the way to Uganda or Angola. The shape resembles almonds and the aroma of a cup of liberica is unforgettable. It’s taste is more than fruity, strongly floral, almost herbal, with a taste of wood complementing this all. It feels like drinking the essence of the very jungle it came from.

Excelsa can be found growing in the wild of South Sudan in medium altitudes. The trees are unusually thick and tall, up to 20 meters. The beans are tear-shaped and they are smaller than those of liberica. This variety is grown in southeast Asia, such as Malaysia and the Philippines. The taste is very intense, sharp and bitter, but still contains fruity tones.

It is very likely that in the future, ways will be found to produce other species commercially. For example, a new species has been described in 2008 in Cameroon - coffea charrieriana - which naturally contains zero caffeine. It is of course still far from commercial use, but one never knows in which direction the market will go.

There is one question which keeps getting brought up: “Which species is the best?”. Or even more often, no question is being asked and it is simply stated that “arabica is the best coffee”. But it is definitely not that simple. The different species have its unique specifics and are loved by many people. Thanks to that, the world of coffee is truly diverse and everybody can find what they like the most. There is nothing easier than simply tasting and tasting until you find your own favourite cup, or simply enjoy everything that nature and the producers can offer.

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