A system is disclosed for de-bunching harvested grapes in bunches on board a harvesting machine. The de-bunching system includes an endless screen (1) that is driven between an upstream transverse shaft and a downstream transverse shaft (2). The screen (1) includes openings adapted to allow the grapes to pass through while retaining undesirable components. The system further includes a driven rotary member (3) overlying the screen which includes debunching fingers (4) to separate grapes from bunches. A device (5, 6, 7) evacuates undesirable components from the screen (1) to a lateral ejection area.
