Arabica / Robusta / Canephora

Photo: Scot NelsonA little exchange on Facebook last week made me think it was time to write a basic guide to the two most common types of coffee. This will be very familiar ground to any readers with a keen interest in coffee, but may be new ground for some.

There are three species of the Coffea genus - three kinds of coffee plant that cannot be interbred. Only two are grown commercially.

The good quality coffee plant is Coffea Arabica, and accounts for about 80% of the world's coffee production. There are a number of varietals within this one species. Most of the time, you get red ripe cherries to pick, inside each of which are two flat seeds. This is the coffee that has the best taste, although the quality of what is grown varies enormously. Please don't make the mistake that some branding and marketing executives want you to make - if it says Arabica on the packet it must be good. The preparation, roast and subsequent

storage can also affect the quality of what you get - but those considerations would take us off-topic. As well as varied quality, there is also varied taste, with different countries of origin, even individual farms, even different preparation methods from the same bean on the same farm - having potentially huge impacts on taste. The range of taste is as wide as in the worlds of wine and whisky, but just less popularly explored.

The other species is Coffea Canephora, although it is often mistakenly referred to as Coffea Robusta. This is the "robusta" coffee. Large amounts are grown in Vietnam, due to the French encouraging its large scale production during their occupation there. The Arabica species can be hard to grow for a number of reasons - it only grows above a certain altitude, is fairly susceptible to pests, and has a lower yield. Robusta is hardier, growing at lower altitudes, with much higher pest resistance. If a farmer simply wants to maximise their yield, this is what they would grow.

It is, however, vastly inferior in taste. Its taste is bitter and rubbery. I'm reminded of one coffee roasting friend who tells the story of another friend who was entering the coffee roasting business. This friend thought he was the latest thing in the coffee world, so my friend set up a cupping session to try out some coffees. One of the beans he put on the table was, cheekily, some robusta. It had come, so my friend said, from a new farm he'd discovered called Ruba Tyros (get it?). His friend was over the moon at how good this coffee tasted. My friend immediately knew there wasn't any grand commercial threat just here.

Although it tastes inferior, it has its uses. Its caffeine content is approximately double to that of Arabica beans. Added in small amounts to an espresso blend (in my opinion, never over 10%, possibly pushing 15%) - provided a good quality robusta is chosen (yes, there are some that are much better than others) - and it adds crema to the shot and increases the caffeine content a little.