Peaberry
also: caracoli, caracol
A single rounded bean that forms when only one of a cherry's two seeds develops; often sorted and sold separately.
Peaberry is the name for a coffee seed that grows alone inside a cherry. Normally a cherry holds two seeds that press flat against each other, giving the familiar flat-sided bean. When only one of the two ovules is fertilized or develops, that single seed has room to grow into a small, rounded, oval shape instead.
Peaberries occur naturally in maybe 5 to 10 percent of any harvest. Because their shape behaves differently in grinders and roasters, many producers sort them out, often by size and shape screens, and sell them as a separate lot. Kenya and Tanzania famously market peaberry as a premium grade.
Do peaberries taste better? There is no firm evidence they do, despite the marketing. The rounder shape can roast a touch more evenly, and the lots are tightly size-sorted, which helps consistency. But cup quality still comes down to variety, origin, and processing, not the single-seed shape. See what-is-a-peaberry for more.