Wine ageing

The choice of container influences the structure and aromas of the wine, as well as its ageing potential.

Ageing in vats, the most common method

Concrete vats have a natural thermal inertia, while stainless steel vats are temperature-controlled and easy to maintain. These materials don't transfer aromas to the wine and their airtightness prevents oxygenation, and therefore oxidation. The wine is then matured in these vats, which are different from those used for fermentation:

• for 1 to 3 months for ageing young wines, known as "primeurs", such as Beaujolais,
• for 10 to 12 months for the ageing of certain wines for laying down where the winemaker wishes to preserve the fruity aroma.

Maturing in oak barrels, a more elitist method

The structural and aromatic properties of oak, as well as its tannin content, make it the wood most commonly used for cooperage in oenology.

• The porosity of the wood allows gentle oxygenation of the wine.
• The more intense the toasting of the barrel staves during production, the more smoky and toasty the wine.
• The diffusion of wood aromas and tannins varies according to the surface area in contact with the wine. The diffusion of aromas and tannins is greater in small and medium-sized barrels, such as feuillette or barrique, and less in large-capacity barrels, such as foudre.

Barrel ageing, which is more common for reds than whites, is therefore destined for great wines to age, such as the crus of Bordeaux, Burgundy or the Rhône.

Aging in jars or carboys

Clay jars (amphorae, kvevris, etc.) oxygenate the wine, but do not add tannins. Some vins doux naturels, such as Banyuls, are matured in dame-jeanne.

Their combination, which varies from wine to wine, embodies the winemaker's signature, which continues to develop as the wine ages in bottle.

Racking(s)

Optional, transferring wine from one container to another with a pump allows :

• its purification of lees and carbon dioxide,
• its oxygenation in contact with the air.

Stirring the must and rolling the barrel

This optional stirring brings the yeasts contained in the lees back into suspension in the oxygenated wine. Reactivated, they will develop the organoleptic complexity of the wine.

Clarification

• By fining: the winemaker purifies the wine by adding egg albumin, which precipitates the fine particles in suspension and carries them to the bottom of the barrel. As a result, the wine is brighter, which improves its quality.
• Filtration: using a conventional plate filter or tangential microfiltration.

Filling

The "angels' share" (the amount of wine that evaporates) calls for the completion of the barrel, known as "ouillage", with the same wine as is raised in it.

Setting the foam

This operation is carried out directly in bottles for sparkling wines, by :

• Champagne method (for champagne),
• ancestral method,
• industrial gasification.