What is arabica coffee? How it differs from robusta

Where does arabica come from?

Arabica comes from the forests of southwestern Ethiopia. Wikipedia's arabica article says wild populations are limited to South Ethiopia, South Sudan and Yemen.

World Coffee Research says historians believe seeds were carried from Ethiopia to Yemen, where coffee was first grown as a crop. From those Yemen plantings came the two big family lines of cultivated arabica, Typica and Bourbon.

Typica traveled with Dutch traders. World Coffee Research traces it from India's Malabar coast to Java in the 1690s. A plant reached Amsterdam in 1706, and another went to Louis XIV of France in 1714.

Bourbon is named for the island now called La Réunion, where the French planted coffee in the early 1700s.

How is arabica different from robusta?

Arabica is less bitter, more acidic, sweeter and lower in caffeine than robusta. The table below uses figures from Wikipedia's species and coffee bean articles.

Genetics explain part of the difference. Wikipedia says arabica is a hybrid of two other species, C. canephora and C. eugenioides, and carries four sets of chromosomes. Robusta has two.

How much of the world's coffee is arabica depends on the year and the source. Wikipedia's arabica article says about 60% of global production. Its robusta article puts robusta at about 45%, so treat both as rough.

Is arabica always better than robusta?

Not always. Arabica is the species specialty coffee is built on. But the species is only one factor, and a poorly grown or badly roasted arabica can still taste flat.

Robusta has its own strengths. It resists pests and disease better and needs less pesticide, which the robusta page covers.

The better question is which arabica. A coffee's variety, origin, process and roast shape the cup far more than the species name on the label.

Why is arabica coffee at risk?

Arabica has very little genetic diversity in cultivation, which leaves it exposed to disease and climate change. Wikipedia says cultivated coffee contains less than 1% of the diversity found in the wild in Yemen alone.

World Coffee Research gives a striking example. In Brazil, which it says accounts for 40% of world production, 97.55% of coffee cultivars descend from Typica and Bourbon.

Coffee leaf rust is the best-known threat. Wikipedia says it causes losses of up to $2 billion a year. World Coffee Research publishes a catalog of 55 arabica varieties, including newer ones bred for rust resistance, such as Batian.

Where is arabica grown?

Arabica grows best in cool highlands in the tropics. Wikipedia says it is usually grown between 1,200 and 1,500 meters, though plantations range from sea level to 2,800 meters.

It prefers an average temperature of 15 to 24°C, with rain spread evenly through the year. World Coffee Research notes that a coffee tree lives 20 to 30 years, so a farmer's choice of variety lasts a generation.

Altitude matters at the grinder too. Counter Culture says higher-elevation, denser coffees need a finer grind, which is one reason recipes are only a starting point.

Does arabica need a special grinder?

No. Arabica grinds the same way any coffee does, and the grinder you need depends on how you brew, not the species.

What changes the grind is roast level and bean density. Counter Culture says lighter roasts are denser and need a finer setting than a dark roast. Our grind converter translates a recipe's setting to your grinder, and the grinder finder matches a grinder to your brew method.

If you are deciding whether a better grinder is worth it at all, why your grinder matters more than your brewer makes the case.