Devatting
Also known as délestage, the oxidative winemaking process in which, after the cap of grape musts, skins, seeds and stems forms on the top of a vat of fermenting wine, the wine is drained through a valve at the base of the tank into another vat and reserved while the remaining solids are allowed to drain for a few hours. The reserved wine is then pumped back into the original tank over the top of the drained skins, seeds and stems. Like punch downs and pump overs, the purpose of devatting is to increase the extraction of color, flavor, tannins and aromas from the solids, as well as aerate the fermenting wine.