Arabica beans differ from robusta beans in three main ways; taste, cost and hardiness. Robusta is mainly used in instant coffee or blended with arabica beans to keep costs down and improve the shelf life. Most people who care about coffee treat the term robusta like a four-letter word, a financial compromise which leads to coffee that tastes less than desirable.
The main reason that robusta beans are cultivated so widely is because they are hardier and produce more yield for the space the crop requires. Robusta beans grow at lower altitudes and because the plant contains so much caffeine it is very resistant to damage from insects. It’s a hardy and reliable crop giving beans which are much cheaper to produce than the more refined and sensitive arabica beans.
Robusta beans are around 40% cheaper to buy than arabica, so the temptation for supermarkets to include it in their blends is obvious. Taste is often compromised until an optimum between price and flavor is reached.
Robusta beans are bitter and contain less sugars than arabica beans, they taste nutty rather than fruity and make bitter coffee similar to what you’d find in coffee that is past it’s prime. Arabica beans, while they can fluctuate too between divine and hellish, they are generally sweeter, with nicer flavor and tones. While you can get robustas that are better than some arabicas, you’re not going to find this happening regularly.
But is there nothing more than this to the robusta bean? Is it nothing but a filler used to keep prices down? Well apparently there is more to it, for some at least. Your robusta is certainly not a drip coffee bean, coffee aficionados are almost unanimous about that.
Espresso on the other hand, is dipping a cautious toe in the water of robusta use, and finding there are some redeeming features to the much maligned bean species.
What Does Robusta Bring To An Espresso?
Robusta is sometimes used to give a thicker crema to the cup, and to give a lasting flavor to the coffee. Robusta beans are excellent for making a more luxurious crema, and for this reason they are regularly used in Italy to make up part of espresso blends.
The trick then is to find a robusta that is neutral enough in taste, blend it with the sweeter arabica beans and you’ve got the best of both worlds: the great flavor of arabica and a crema you could float your biscotti on. Excellent news.
Another difference between these types of bean is in the caffeine content. Arabica beans contain much less caffeine than robustas. This means that when they are used in espresso, they can give the shot a little more punch. Given that it is most common for espresso to be made with dark roasted beans which have much of the caffeine roasted away, the use of robustas can really give the drink its mojo back.
So maybe there is a little room for robusta beans in good coffee. All that’s required is to find a variety which doesn’t taste of anything at all and then it’ll make a very useful addition to your espresso. It can’t hurt to experiment with it, after all, it certainly has qualities that can add a lot to your cup.
Whether there will ever be a robusta blend to compete with the top end arabica beans is questionable and hotly contested, but there’s only one way to find out.