The must undergoes two débourbages (settlings), one at the press house immediatly after pressing and the second, a débourbage à froid, in stainless steel tanks at 6°C over a 24 hour period. A slow cool fermentation with the temperature kept under 18°C takes place in stainless steel with each variety and each village kept seperate. The wine undergoes a full malolactic-fermentation prior to final blending. Secondary fermentation takes place in bottle at 9°C in the deepest Pol Roger cellars (33 metres below street level) where the wine is kept until it undergoes remuage (riddling) by hand, a rarity in Champagne nowadays. The very fine and persistent mousse for which Pol Roger is renowned owes much to these deep, cool and damp cellars.