1) Pruning

Of all the commercially grown plants, the vine is without doubt the most sensitive to its environment. It requires constant care. Pruning begins around six weeks after the grape harvest to provide more mature grapes and thus better quality wine. The work continues until March. From mid-March to the start of May, the vine shoots are attached to, and trained along, wires to "discipline the vine". 

2) Budding

Around mid-April, the vines come into bud. The young green shoots will have to withstand the spring frosts which, in some years, can cause significant damage. Bud selection takes place in May and June, after the first buds have appeared.

This is a period of long, patient observation, during which the most promising shoots are individually selected and the others eliminated.

Thus the shoots chosen will grow more vigorously.

3) Flowering

Flowering is a capricious and demanding process that usually lasts twelve days or so in June. Mumm’s own growers keep a careful watch during this difficult stage, as cold or damp weather can endanger the harvest and cause substantial losses through the vines’ failure to set fruit or through uneven fruit formation.

In summer the vines are tied and topped, their leaves being thinned out to allow the sunlight to reach the fruit more easily. In September the harvest comes round again.

4) The environment

To yield high-quality grapes, the vines need protection against the various diseases and pests from which they can suffer – insects, grape caterpillars, mildew, oidium and rot. While putting in place such protection, Maison Mumm is careful to limit the use of remedies to ensure the maintenance of vine quality doesn’t compromise the environment.

Maison Mumm has nearly 218 hectares of vineyards rated at 98% on the champagne quality scale.
These are mainly sited in the eight most renowned Grands Crus in Champagne: Aÿ, Bouzy, Ambonnay, Verzy, Verzenay, Avize, Cramant and Mailly-Champagne. These holdings cover 25% of Mumm’s production needs. The remaining 75% comes from independent growers with whom the company has developed strong ties.

This combination of its own vineyards and external supply enables the Maison Mumm to maintain a consistent style and continue its philosophy of close scrutiny over grape quality. At Mumm, the Cellar Master can call on raw materials of the very best quality from a range of sources.

1) Grape picking

Usually, the grapes are picked between the end of September and mid-October, around 100 days after the vines have flowered. This is when the grapes are ripest. As required by the champagne appellation rules, picking is exclusively by hand, vineyard parcel by vineyard parcel, bunch by bunch. For about three weeks, the Maison Mumm employs approximately 1,000 grape pickers.

2) Pressing

The grapes are pressed, with only their juice collected during the process.

Care must be taken not to apply too much pressure, as this could result in the grape skins and their pigments coming into contact with the juice. From the 1840s, Mumm built press houses close to the vineyards, a practice that continued until around 1910. The company recognised that pressing the grapes soon after picking reduced the risk of damage from the long journey to the winery or from the weather. A whole year’s work in the vineyards could be lost all too easily.

Today, Maison Mumm still has seven traditional presses from that time, known as ‘Coquard presses’, near its vineyard holdings.

3) Racking

After pressing, the grape juice must have any organic residue, pips or skins from the grapes, and any vineyard soil removed. This is known as “racking”.

The grape juice is left in vats at a temperature of 10-15°C for about 16-18 hours. Any particles fall to the bottom by the action of gravity. The resulting clear juice, or “must”, is then moved to Mumm’s vinification vats.

1) Fermenting more than once

After pressing, the must is stored in vats for about two weeks at between 18°C and 20°C for the alcoholic fermentation process. Natural yeasts convert the sugar in the must into alcohol and carbon dioxide, turning the must into wine. Mumm is careful to keep the different crus and grape varieties apart, ensuring the character of each terroir is preserved until blending. The company has always allowed a second fermentation, known as malolactic fermentation, to occur. This is a natural process during which the malic acid turns into lactic acid, reducing acidity and making the wines softer. This second fermentation is optional, rather than a requirement of the champagne appellation rules.

The malolactic fermentation directly affects the style of Maison Mumm’s wines, leaving them softer without making them any less fresh or lively.

2) Clarifying

Following the fermentations, the wines are transferred to other vats to remove any remaining yeast or solids that could affect the taste. The wines are called "still wines" after clarifying, as they have yet to acquire their sparkle.

3) Blending

Blending involves the art of combining still wines of different grapes and growths to create champagnes of consistently high quality that reflect the house style of Mumm. This subtle art is considered the "signature" of any champagne house and its Cellar Masters. To reach the blending stage, around 2,000 samples are tasted, noted and memorised every year by the Chef de Caves and his team of expert winemakers. Up to 77 different crus go into the Cordon Rouge blend each year.

To ensure Mumm's champagnes retain their usual depth and freshness year after year, reserve wines are carefully kept. These help soften any contrast between the different years’ wines during blending. In certain years when the harvest is exceptionally good, the Cellar Master may decide to create a vintage, for which only wines of that year may be blended.

1) Bottle fermentation

The still wine becomes champagne while hidden in the depths of Mumm's cellars. The liqueur de tirage triggers a second alcoholic fermentation. Over the course of a month, at a constant temperature of 11°C, bubbles gradually form. This is how the wine becomes sparkling. Its alcoholic strength increases from 11% to 12%. The quality of this fermentation will determine how gentle the sparkle of Mumm's champagnes is, as well as their degree of freshness and depth. As the bubbles are formed, so the pressure inside the bottle increases, reaching as much as 6 bar.

2) Maturation

The bottles are stored on their sides in Mumm’s cellars.

Dug by hand out of the chalk, these cellars comprise 25km of galleries in total, taking 70 years to excavate.

Today, they house nearly 25 million bottles.

Over many months, the wines develop their richness of taste and aromatic complexity. During the ageing process, the yeast forms a deposit in the bottle. It’s through contact with this deposit that the wine acquires its rich taste and distinctive character. 

The winemaking team prefers to age the champagnes for longer than the legal minimum to create wines of perfect maturity. This means two and a half years for Cordon Rouge instead of eighteen months, and almost five years for vintage champagnes rather than three years. Another instance of the quality of Mumm champagne.

3) Dosage

A liqueur de dosage, made from a mixture of cane sugar and old Mumm champagne, is added to the wine.

An integral part of the company’s expertise, the exact composition of the various formulas of liqueurs de dosage is a secret known only to the Cellar Master. The proportion of sugar added dictates the style of champagne produced – Brut or Extra-Brut, Sec or Demi-Sec. 

The liqueur used at Maison Mumm  is drier than most. At between 6g/l and 9g/l instead of the usual 12g for a Brut champagne, it allows the full subtlety of the blend to come through.

Finally, Chef de Caves insists that all champagnes be left to rest before shipping, thereby letting the liqueur blend properly with the wine.

The bottle sizes still bear the names given to them by champagne houses at the start of the 20th century. With the smallest first:

• Quarter bottle = 18.7 or 20cl, depending on the country
• Bottle = 75cl
• Magnum = 1.5 litres
• Jeroboam = 3 litres (named after the founder and first King of Israel)
• Methuselah = 6 litres (named after Noah’s grandfather)
• Salmanazar = 9 litres (named after the King of Assyria)
• Balthazar = 12 litres (named after the regent of Babylon)
• Nebuchadnezzar = 15 litres (named after the King of Babylon)

"Only the best" was Georges Hermann de Mumm’s maxim.

To this end, the Maison Mumm has been working with national scientific research bodies such as the INRA and CNRS, as well as Météo France, to develop new procedures, many protected by patents.

Mumm's researchers investigate the importance of the terroir to champagne production, combating adverse weather conditions, and improving fruit quality, among other subjects, in their constant quest for excellence. The Maison Mumm has also achieved ISO 9001 certification for its quality management systems.