Nearly all the coffee in the world comes from two species: Coffea arabica and Coffea canephora, better known as robusta. Specialty coffee has spent decades teaching people that arabica is the good one. The truth is messier, and Italian espresso bars have known it all along.
Two Very Different Plants
Arabica is a natural cross between robusta and another species, Coffea eugenioides, and it carries four sets of chromosomes, 44 in all. It can pollinate itself. That’s handy for farmers, but it leaves the species with little genetic variety and weak defenses against diseases like leaf rust. Robusta has the usual two sets, 22 chromosomes, and can’t pollinate itself, so every tree comes from a cross and the species is far more diverse.
They like different places, too. Arabica does best at a mean temperature of about 18 to 21°C and is mostly grown between roughly 900 and 2,100 meters up. Robusta is the lowland coffee, grown from sea level to about 800 meters, and it was long thought to love heat. That’s only half true. A 2020 study of about 800 farms in Vietnam and Indonesia found robusta yields peak at around 20.5°C and drop about 14% for every degree above that.
What’s in the Bean
| Green bean, share of dry weight | Arabica | Robusta |
|---|---|---|
| Caffeine | About 1.2% on average | About 2.2% on average |
| Sucrose | 5 to 9.5% | 4 to 7% |
| Oil | About 15% on average | About 10% on average |
| Chlorogenic acids | 4 to 8.4% | 7 to 14.4% |
That table explains most of the difference in the cup. Robusta has less sugar and more of the compounds that taste bitter and astringent, and caffeine itself is bitter. Arabica has more sugar and oil, which roast into sweetness and aroma. The averages hide a lot of overlap, though. A carefully grown robusta can beat a poor arabica.
Who Grows Which
Estimates for the 2025/26 season put arabica at a little over half of world output and robusta at a little under half, depending on who’s counting. Robusta’s share has climbed from about a quarter in the early 1990s to 40% or more. Brazil leads arabica, followed by Colombia, Ethiopia, Honduras and Peru. Vietnam leads robusta, with Brazil second, then Indonesia, Uganda and India. Brazil’s robusta crop hit a record in 2025/26.
Why Italian Espresso Blends Use Robusta
Price is the obvious reason. In August 2026 robusta sold for a little over half the price of Brazilian natural arabica, and futures are still far apart. But Italian roasters don’t use it only to save money. Robusta adds body and caffeine, and it helps a shot hold its own under milk. France, Spain and Greece have long blended it too.
Then there’s crema. The usual line is that robusta makes more of it. Lab tests are less sure. One study found no real difference in how much foam the two produce, but robusta’s lasted much longer, about 49 minutes against 34 at a medium roast. That stability is part of why a robusta blend looks so good in the cup.
For a cortado, a blend with some robusta makes sense. Milk mutes flavor, and robusta’s weight and bitterness cut through it in a way a delicate arabica often can’t. Most specialty cafés still pour 100% arabica, and there’s a small movement for high-quality “fine robusta” too. The quickest way to decide is to try both in the same drink, side by side.