Welcome to 25 kilometers
of cellars built
14 meters underground
The noble art
Once they are filled, the champagne bottles are stored on their sides in Mumm’s cellars, ready for aging. The cellars comprise 25 km of galleries in total, which took 70 years to excavate. Today, they house nearly 25 million bottles.
Over many months, the wines develop their rich flavors and aromatic complexity.
Contact with the yeast deposits from the secondary fermentation adds elegant nuances such as brioche and hazelnut.
Champagne must be aged for a minimum of fifteen months, but at Maison Mumm we prefer to age champagne for much longer, to create wines of perfect maturity.
According to champagne specifications, a vintage champagne must be aged for a minimum of three years. At Mumm, aging lasts at least 5 years and can go up to 10-12 years for certain prestigious cuvées.
The aim of this process is to concentrate all the deposits that have built up in the bottle during aging in order to facilitate their extraction.
To do so, the bottles are tilted neck down at a 20°angle. Then the bottles are rotated once a day, never more than half a turn. They are gradually tilted more and more to reach an angle of 60°.
A 75cl bottle is rotated about 20 to 25 times before leaving the cellar.
Once the deposits have settled in the neck of the bottle, they can be removed.
The neck of the bottle is immersed in a tank of brine, refrigerated at -25 degrees Celsius. After a few seconds, the champagne in the neck of the bottle freezes with the deposits trapped inside making them easy to extract.
The bottle is uncapped and the frozen plug ejected under the effect of the pressure.
Finally, it’s time for The dosage
A ‘liqueur de dosage’, made from a mixture of cane sugar and previous Mumm champagne, is added to the wine. This liqueur allows the champagne to fully express itself.
An integral part of the House’s savoir-faire, the exact composition of the various formulas of liqueur de dosage is a secret known only to the Cellar Master. The proportion of sugar added dictates the style of champagne to be produced – Brut or Extra-Brut, Sec or Demi-Sec.
The liqueur de dosage used at Mumm is drier than most.
At between 6 and 9 grams per liter instead of the usual 12 for a Brut champagne, it allows the full subtlety of the blend to come through.
A little more patience and rest
Finally, the Cellar Master insists that all champagnes are left to rest before shipping, thereby letting the liqueur blend properly with the wine.
The final touch: the label
Once aging is finished, each champagne bottle is signed with the emblematic Mumm Red Sash.