The other week I had the chance to be assisting during a Q Graders course, not for Arabica, but for Robusta coffee. The Q coffee system measures and standardises quality for Specialty grade Arabica and for Fine Robusta coffees. The Robusta programme designed from the Specialty Coffee Association of America (SCAA) and the Uganda Coffee Development Authority (UCDA) exists from 2010 and by far there are around 185 Robusta graders around the world. The course was held at Bernhard Rothfos Intercafé in Zug Switzerland with instructor Clare Rwakatogoro. It was the first Q Robusta course held in Europe, needless to say – extremely interesting.
Robusta is a quite discussed topic in the specialty coffee circle in Switzerland. However it is crucial to understand that Robusta and Arabica are different species, therefore they shouldn’t be compared to each other. That said, it is very difficult to disregard everthing you’ve already learned about Arabica, comparison of some sort is inevitable.
Similar to Q Arabica, there are a lot of tests you have to pass in order to become a Q Robusta grader – 4 cupping sessions, 4 triangulations, green coffee grading, roasted grading, roast identification, organic acid matching pairs test, sensory skills and an olfactory test (to learn more about the Q system here).
The UCDA/SCAA cupping protocols for Robusta are a bit different than the ones for Arabica – the dose is higher (8.75g/150ml) and the grind is coarser. Also sample roasting takes more time – 9 to 14 minutes (8 to 12min for Arabica). The protocols are designed to serve as a standardized procedure for achieving consistent results and to make Robusta taste its best.
There are a few big differences in the way how it is being scored. In Robusta we’re talking about the four main tastes – sweet, sour, salt and bitter – and how they are complimenting each other. Broadly said, robusta is known for it’s higher level of potassium (the saltiness in the cup) and chlorogenic acid (the bitterness in the cup); lower level of organic acids and sugars. These tastes are reflected on the scoring sheet as ratios marking the relative balance of the sensations. We have the salt/acid ratio, where a very good robusta will have lower saltiness and higher acidity, and the bitter/sweet ratio, where the optimum balance would come from a lower bitterness and high sweetness.
What also made an impression on me was that on some of the scales for marking the coffee’s attributes there are words input, like as in to show from where to where do the scales go. For example, when marking aftertaste there’s the taste descriptor brackish at the beginning and savoury at the end. I find them quite confusing, I wouldn’t like coffee to be either of those.
Marking uniformity and clean cups is very different as well. You have to be very much more liberal when marking Robusta. If something does not strike out as a defect, you don’t mark it.
Speaking of disregarding what I’ve learned for Arabica, the olfactory test was the most baffling. In the enzymatic aromas there were some like strawberry, banana and pineapple, there was pine aroma in the sugar-browning…I don’t remember all of them. What I do remember though was that the aroma of pepper (from the dry-distilled aromas) when found in Arabica it’s not necessarily negative, whereas in Robusta it is. The aroma of pepper is found usually in commercial grade Robustas, but not in higher quality ones…that’s at least how I explain it.
Overall learning about Robusta was very interesting, There’s a lot of room for interpretation still…I’m sure after some time the system is going to get more efficient and sophisticated.