tirage in a closed tank

It is the tank counterpart of bottle tirage, where the same mixture is filled into hermetically closed bottles.² The tirage liqueur brings the sugar, and the yeast then carries out a secondary fermentation, which the OIV defines as alcoholic fermentation in hermetically closed containers.² In the OIV description of the closed tank method, this fermentation is followed by clarification and isobaric bottling.¹ In the EU, the CO2 of sparkling and quality sparkling wine may come only from fermentation of the cuvée.³ The whole process is described on the tank method page.