What Causes Black Beans in Green Coffee?

Black beans are serious green-coffee defects commonly associated with problems such as overripe or damaged fruit, fermentation issues, or other adverse conditions during production and processing.

They can contribute harsh, unpleasant flavors and are therefore important in physical grading.

Sorting at cherry and green stages helps remove them, but prevention begins with good harvesting and processing.

Buyer takeaway: ask for defect counts and the grading protocol used. A clean-looking sample should still be cupped because physical and sensory quality need to agree.