What you need to know about Arabica coffee and Robusta coffee
Arabica and Robusta are the two species of coffee plant used to make virtually all the coffee bean types you will find.
There are many more, but virtually all the coffee grown commercially is made up of these two. There's a third called Liberica, but you’ll rarely if ever come across it, so can ignore it for most purposes. Some consider a Excelsa a fourth, but it’s technically a variant of Liberica, although with very different flavour.
Most coffee grown around the world is Arabica coffee – around two-thirds to three-quarters. The rest is Robusta coffee, apart from around 2% Liberica.
Many people choose Arabica coffee, because they believe it taste better than Robusta. While it’s true that good Arabica usually tastes better than good Robusta coffee, things aren’t so simple. Good Robusta beans can taste better than average Arabica, poor examples of both are equally unpalatable, and a blend of both can range from exquisite to dire.
Robusta coffee is cheaper, because the crops are hardier, and are less “fussy” about where and how they’re grown. It’s used to good effect in some blends to enhance the flavour. But it’s also commonly used in blends and instant to keep prices low.
Robusta beans have more caffeine than Arabica coffee, so are often used in espresso blends. (Caffeine levels aren’t as high in espresso as other brewing methods).
Should you care what species your coffee beans are? In our view, no – let the roasters deal with that, and choose based on flavour. You can’t automatically infer anything about the bean species from whether the coffee tastes great or lousy.
The next time someone says Arabica coffee beans are the only great coffee beans to buy, you know the answer is that it doesn't have to be the case.