Definition: pigeage

The purpose of punching down is to keep the cap constantly moist to promote the extraction of anthocyanins and tannins, which are responsible for colour.
This laborious operation is now often mechanised, even computer-programmed (automatic punching down).
Pushed by the carbon dioxide produced during fermentation, the solid particles rise to the surface. Pushing them back down into the liquid, sometimes several times a day, is known as pigeage.