The base wine is put into pressurized tanks for the prise de mousse; it ferments in these for 18 - 20 days, with the aid of selected yeasts, at controlled temperatures of between 14 and 16° C. Once the desired pressure has been obtained (around 6 bar) the wine is chilled to -4° C in order to block the fermentation and encourage stabilization. It is then kept at a controlled temperature for at least one month, so as to favor its natural maturation in contact with the lees. At the end of this process, it is filtered and undergoes isobaric bottling.