What is colour sorting in green coffee?

Colour sorting is the dry milling step where defective beans are identified and removed based on visual appearance - by optical sorting machines, by hand, or both.

Optical sorters use high-speed cameras and precision air jets to scan beans moving through a chute. Any bean deviating from the target colour - black beans, white or pale beans, visibly damaged material - triggers an air jet that ejects it mid-flight. Modern machines process tonnes per hour with high accuracy.

Hand sorting catches what the machines miss: irregular shapes, partial defects, subtle discolourations that optical systems don't flag reliably. European Preparation (EP) designates coffees that have received an additional hand-sorting pass on top of machine processing. The number of sorting passes and whether hand sorting is included directly determines the defect count of the exported lot - which is why it appears on the specification.