Fermentation vat

An automatically operating fermentation vat for winemaking establishments comprising a main vat (2), an upper vat (4) over the main vat, an uplift pipe (8, 12, 10, 24, 26) for conveying a fermenting liquid from the bottom of the main vat to the upper vat, means (16, 14, 18) for discharging this liquid from the upper vat into the main vat in such a way that it sprays a layer of marc floating on the surface of the main vat, and injector means (20, 32) associated with the uplift pipe for injecting oxygen-containing gas into the liquid as it flows through this pipe, characterised in that the uplift pipe has a first outlet aperture (24) which feeds the liquid into the upper vat (4) and a second outlet aperture (40) which feeds the liquid into the fermenting liquid in the main vat, selective valve means (22) being associated with the uplift pipe for selectively directing the liquid into the upper vat or into the main vat, or into both at the same time through the two said outlet apertures.