The peaberry coffee bean is technically a defect, or mutation, of the coffee bean. Where most coffee comes out of the cherry as two seeds, with a flat front and round side, peaberries come out as a single round bean with no flattened surface. This is mostly an abnormality within the coffee cherry and only occurs around 5% in any given crop globally. Peaberries come from the same crops as flat beans do, and it is not until the coffee cherries are processed and sorted that peaberries are found within the crop, but ultimately a small percentage end up having this unique, yet flavorful distinction.
While it’s not known exactly how peaberries form in the coffee cherry, it’s thought that pistils in the coffee plant fall off for any number of reasons, which then causes one seed to form inside the fruit. Because there’s only one seed in the coffee fruit instead of two, all the nutrients get concentrated into a denser space leading to richer bodies from peaberries.
Many different variables go into making a great quality peaberry coffee, and it should never be assumed that peaberry beans are automatically better than flat beans, since often peaberries can be just as average or poorer quality than flat bean coffee. Just because the peaberry is rarer than flat beans, by no means makes it better. But there are certainly qualities in peaberry coffees that are unique to its body and cannot be replicated in other types of coffee.
Region, variety, processing, altitude, and roast profiles all go into determining how great your peaberry coffee comes out in the cup. Tanzania and Hawaii are perhaps the best known for their peaberry coffees, and there’s good reason for that. Both regions grow their coffee over 3,000ft. above sea level, use quality arabica coffee from some of the best varietals, such as bourbon, kent, and typica, as well as using washed processing methods to bring out a crisper, well-rounded cup with a full body.
It’s thought that peaberries roast better because of their rounded bodies being naturally conducive for most roasting machines that use rotating drums since the rounded coffee bean more easily rotates and thus receives a more even dispersal of heat during the roast. Because peaberries tend to be denser than their flat counterparts, heat, endothermic and exothermic reactions, play an even more pivotal role in how the peaberry coffee comes out.
The peaberry name lends itself to something exotic, bold in flavor, yet this tiny little bean that's flourished in the coffee cherry to create some of the most unique cups of coffee known to the coffee industry. It took quite a bit of effort picking, sorting, and ensuring that each peaberry was separated from its flat counterparts, which often lends to why peaberries cost a little more. There are many regions that court their own peaberries, and here at Volcanica we try to feature as many as possible because of the wide-variety of tasting notes that come out of the peaberry coffee.