What is arabica coffee?
As a reader of this website, you are no doubt aware of the two most commonly used beans for making coffee – Arabica and Robusta. However, what is Arabica coffee and Robusta coffee and is Arabica really “better”?
Arabica and Robusta are terms referring to the “species” from which the coffee belongs. The coffee plant is a shrub that belongs to the family of Rubiaceae, genus Coffea. Some dozens of species of the genus Coffea are known, but only two are significant in economic terms: Coffea arabica and Coffea canephora (commonly known as Robusta).
Coffea arabica is native to central Ethiopia. The name Arabica was given to this species of coffee by the botanist Carolus Linnaeus who incorrectly believed that it originated on the Arabian Peninsula in modern-day Yemen.
It is believed that Arabica coffee was the first species of coffee to be cultivated, and is by far now the dominant cultivar, representing some 70 – 80% of global production.
Arabica coffee production
The coffee plant grows in countries that lie between the two Tropics, where there are no seasonal changes. Arabica coffee is widely naturalised in areas outside Ethiopia, in many parts of Africa, Latin America, Southeast Asia, China, and assorted islands in the Caribbean and in the Pacific, in what is commonly known as the coffee belt.
Gourmet coffees are almost exclusively high-quality mild varieties of Arabica coffee, and among the best known Arabica coffee beans in the world are those from Jamaican Blue Mountain, Colombian Supremo, Tarrazú, Costa Rica, Guatemalan Antigua, and Ethiopian Sidamo. Espresso typically is made from a blend of Arabica and Robusta beans.
Climate change—rising temperatures, longer droughts, excessive rainfall—appears to threaten the sustainability of arabica coffee production.
What are Arabica Beans?
The coffee bean is actually the seed of the coffee plant, found inside a red fruit often called the cherry. Each cherry contains two seeds (beans) surrounded by a membrane called the parchment and a layer of sweet pulp. Arabica beans are fairly flat and elongated, with a sinuous groove.
Coffea arabica takes about seven years to fully mature and does best with 1.0–1.5 meters (about 40–59 inches) of rain, evenly distributed throughout the year. It is usually cultivated between 1,300 and 1,500 m altitude, but plantations grow it as low as sea level and as high as 2,800 m.
The plant can tolerate low temperatures, but not frost, and does best with an average temperature between 15 and 24 °C (59 and 75 °F). Commercial cultivars grow to about 5 m, and are frequently trimmed as low as 2 m to facilitate harvesting. Unlike Robusta, Arabica prefers to be grown in light shade.
Two to four years after planting, Coffea arabica produces small, white, highly fragrant flowers. Flowers opening on sunny days result in the greatest numbers of berries.
On well-kept plantations, over flowering is prevented by pruning the tree. The flowers only last a few days, leaving behind only the thick, dark-green leaves. The berries then begin to appear. These are as dark green as the foliage, until they begin to ripen, at first to yellow and then light red and finally darkening to a glossy, deep red. At this point, they are called “cherry” and are ready for picking.
The trees are difficult to cultivate and each tree can produce from 0.5 to 5.0 kg of dried beans, depending on the tree’s individual character and the climate that season.
On Java Island, trees are planted at all times of the year and are harvested year round. In parts of Brazil, however, the trees have a season and are harvested only in winter. The plants are vulnerable to damage in poor growing conditions (cold, low pH soil) and are also more vulnerable to pests than the Robusta plant.
Arabica and Robusta
There are over 100 coffee species, however the two main ones that are widely produced and sold are: Coffea Arabica and Coffea Robusta.
The name “Arabica” isn’t in and of itself an indicator of final beverage quality. Indeed the typical Italian espresso uses the bitter darker roaster of the Robusta bean. Arabica coffee is shade-grown in the mountains above 600 meters, and therefore more difficult to cultivate and harvest than plantation grown Robusta.
The greatest coffees in the world are Arabica, but there are lots of inferior Arabica coffees which are not suitable for speciality coffees. Robusta (Coffea Canephora) is typically cultivated at lower altitudes and has been engineered so that it can be grown on relatively flat plantations, so it is easier to harvest and less labour intensive. It has a stronger and harsher taste when roasted, often described as burnt wood, grain-like and bitter.
Robusta is more disease and pest-resistant, an important characteristic given the price instability of coffee commodities due various factors. This resilience can be explained in part from its higher caffeine content and it typically produces a larger crop than Arabica. Green Robusta beans are typically 40-50% cheaper than Arabica beans. The quality of Robusta coffees range from the lowest grades suitable only for inexpensive instant coffee to higher grown, washed Robusta considered suitable by some roasters to extend their blends. Good horticultural practices could produce better quality Robusta but one would not expect to find any Robusta that compares favourably to good Arabica.
Arabica vs. Robusta
Much like wine, coffee flavour is affected by soil, altitude and other climatic factors. There are 65 coffee producing countries between the Tropics of Cancer and Capricorn and in Ethiopia alone there are reportedly over 10,000 varietals.
It is a fact that all the best tasting coffee is made from Arabica beans which are naturally mild and aromatic, with a rich round pallet and imbued with subtle and delicate flavours that lean toward the fruity side.
Robusta beans yield a harsher, bitter-tasting cup with significantly more caffeine. Robusta is used by some coffee producers because the plants, being hardier and easier to grow and harvest produce a cheaper, though less desirable bean. Robusta is more disease and insect resistant than Arabica because it produces as much as three times the amount of caffeine as Arabica plants. The extra caffeine helps protect the Robusta coffee plants from pests because caffeine is a powerful insecticide and anti-microbial agent. So the choice to use Robusta is driven by economic decisions, not by quality concerns.
Difference between Arabica and Robusta
Here’s a list on differences between the two species
- Taste: one reason that the taste is not as good for Robusta as it is for Arabica is that it has more caffeine. Which may sound like a positive thing but caffeine carries a bitter taste which makes it an unpleasant drink. In fact, the Robusta bean has 2.7% caffeine content, almost double the 1.5% of Arabica. (Visit SCAA website for more information about the flavour wheel.)
- Growing Conditions: A big difference between Arabica and Robusta Coffees are the conditions in which they are grown. Arabica coffee is grown anywhere upwards of 600+m on mountaintops and tropical environments. Whereas Robusta coffee is grown anywhere from sea level to around 600m. Robusta coffees also produce a harder fruit and thus are not as susceptible to pest as Arabica.
- Cultivation: About 75% of the world’s coffee production is Arabica, about 25% being Robusta. Brazil is the most significant Arabica producer and Vietnam produces the most Robusta.
- Bean Traits: Arabica coffee beans are slightly larger and have an elliptical shape compared to the smaller, more round Robusta beans. Structural differences also exist between the beans, which may explain why both beans roast differently under identical conditions.
- Plant Height: Arabica usually grows between 2.5 – 4.5 meters compared to the 4.5 – 6-meter height of Robusta.
- Caffeine Content: Robusta coffee actually has higher caffeine content. Robusta is used quite frequently in instant coffee and as a blend additive to help give a specific coffee mix an extra “jolt.” In fact, Robusta has about 2.7% caffeine content while Arabica holds 1.5%
- Lipid & Sugar content: Arabica contains almost 60% more lipids and almost twice the concentration of sugar than Robusta. This factor also probably has a big impact on why we prefer the taste of Arabica.
- Chlorogenic acid (CGA) content: CGA is a significant antioxidant and an insect deterrent. Robusta has 7-10% CGA content and Arabica has 5.5-8% CGA content.
- Price: From a price perspective, green beans of Robusta are about half the price of Arabica green beans on the commodity market.
Robusta has a higher yield and is less sensitive to insects – the extra caffeine is a chemical defence for the coffee seed as the quantity in the Robusta is toxic to bugs. All of these factors help bring up the supply and lower the input costs for farmers to produce. With this more attractive price point, a lot of roasters back in the day would add Robusta to their blend in an attempt to reduce their costs and increase their profits. When coffee was initially sold in the 1900s the quality of coffee slowly and slowly deteriorated in an effort for companies to squeeze the most profit.
Nowadays, it is not often you will find Robusta in an upmarket coffee blend. If you are drinking instant coffee? Well, that is probably all Robusta. In your espresso blend? Robusta is still widely used as part of espresso blends – specifically Italian style blends.
One thing to note is despite the association with Arabica of being higher quality, and Robusta as being lower quality; it is not always the case. Top-notch speciality Robusta coffee will usually taste as good as or better than low-end Arabica. However, high-end Robusta isn’t widely used or available. Rather, Robusta is usually used as a filler or cost reducer. Of course, ‘taste’ is a matter of opinion, and many people do actually prefer the stronger and bitter taste that comes from the Robusta bean.
For more article related to Arabica coffee, click here
For more article related to Robusta coffee, click here