Fermotan is a vinification tannin with antioxidation and colour stabilization properties. From the onset of fermentation, anthocyanins are extracted faster than tannins. In order not to extract these colour compounds in vain, it is imperative to protect them from the oxygen and steer them towards stable polymerization forms, such as those with proanthocyanidins. The synergy among the 3 classes of tannins (ellagic, proanthocyanidinic and gallic), exerts a triple protective action towards the anthocyanins.