Abstract: An apparatus and a method for sorting particles into quality classes are disclosed. The apparatus comprises a measurement device (400) for determining at least one analytical property of said particles. A transport device (300) transports the particles past the measurement device. A sorting device (500) is operatively coupled to the measurement device and sorts the particles into at least two quality classes based on the analytical property. To achieve rapid and reliable transport, the transport device comprises a transport surface (310) configured to move in a transport direction. The transport surface has a plurality of perforations. The transport device further comprises a pump (130) for applying a pressure differential to these perforations, to cause particles fed to the transport device to be aspirated to the perforations and to be transported on the transport surface past the measurement device to the sorting device.