There are a number of subtypes of the Robusta bean, each exhibiting a unique set of characteristics. The same is true of Arabica beans. Robusta varieties sometimes exhibit greater immunity to disease and increased production capacity in comparison to Arabica. Growing well at lower altitudes, Robusta thrives in areas where Arabica would be devastated by fungus and other diseases and pests.
Robusta is a stouter plant, about twice the size of Arabica and it grows well at higher humidity. After flowering, the berries take almost a year to ripen. Robusta is self-sterile, therefore, cross-pollination by wind, bees and other insects are necessary for the plant to reproduce.
Despite containing less caffeine than Robusta coffee beans, Arabica beans, especially in Western culture, are considered far superior in taste, smoother and less acidic. According to the ICO, more than 60 per cent of the world coffee production comes from Arabica cultivators.
Arabica grows from a glorious smelling flower that appears after a couple of years and produces ellipsoidal fruits, inside which are flat coffee beans. The shrub can grow up to 5 meters but to make it commercially viable it is usually pruned at around 1.5M to 2M.
Arabica has two sets of chromosomes, so it is capable of self-pollination, which means that it’s from generally remains fairly stable because cross-pollination is less probable. Of the two most common varieties of Caffea arabica, Typica was the first variety of the species discovered and therefore, is regarded as the original coffee. It is a low-yielding variety that is valued for its excellent cup quality.
Bourbon varieties are often prized for their complex, balanced aromas and have spawned many high-quality mutations and subtypes, such as the natural mutations of Caturra, San Romon and Pacas.
Robusta is not a coffee species but a common ‘varietal’ of Coffea, Arabicas more street-smart younger brother. Despite its flavour being considered less refined Robusta sometimes used in espresso blends because it is known for producing a better crema – the creamy layer and packs way more caffeine than Arabica.
Growing well at lower altitudes, Robusta thrives in areas where Arabica would be devastated by fungus and other diseases. Robusta is high antioxidants which protect the coffee from this. The Arabica plant is a stouter plant and about twice the size, it grows well a higher humidity. After flowering the berries take almost a year to ripen. The Robusta is self-sterile, therefore cross-pollination by wind and bees and other insects is necessary for the plant to reproduce.