Why are some wines sparkling?

Why are some wines effervescent?

Sparkling wine bubbles fascinate, enchant and accompany festive moments. But where do they come from? Why does a sparkling wine sparkle while a still wine remains flat? Behind this effervescence lies a precise know-how, the result of different winemaking methods. In this article, La Sommelière explains how bubbles are created in wine... and why not all sparkling wines are alike.

The origin of bubbles: fermentation

A wine's effervescence comes from the transformation of sugar into alcohol by yeast, which also produces carbon dioxide (CO₂). In a still wine, this gas is evacuated. In an effervescent wine, it is trapped in the bottle or vat, creating the bubbles when opened.

There are several methods for making effervescent wine, each giving a very distinct style.

1. The traditional (or champenoise) method

This is the method used to make champagne, as well as crémants (Loire, Alsace, Burgundy, etc.). It consists of a second fermentation in the bottle, thanks to the addition of a liqueur de tirage (sugar + yeast).

Key stages :

• Alcoholic fermentation of the base wine.

• Bottling with tirage liqueur.

• Prise de mousse (second fermentation).

• Aging on lees for several months (minimum 15 months for champagne).

• Disgorging and addition of liqueur d'expédition (to adjust the sugar content).

• Resting and marketing.

Result: fine bubbles, creamy texture, great aromatic complexity.

2. The Charmat (or closed tank) method

Used for wines such as Prosecco or certain Moscato d'Asti. Here, the second fermentation takes place in a pressurized tank, not in the bottle.

Advantages :

• Faster and less costly.

• Preserves primary aromas (fruit, flowers).

Result: larger bubbles, fresher, fruitier wine, less complex than champagne.

3. The ancestral method

Also known as pétillant naturel (pet-nat), this method involves bottling wine during fermentation, without adding sugar or yeast.

• Fermentation ends naturally in the bottle.

• There is no disgorging: the lees can remain in the bottle.

• The wine may be slightly cloudy.

The result: irregular bubbles, a wine that is often more rustic, authentic and natural.

4. Carbonation (addition of CO₂)

Less noble, this method involves adding carbon dioxide artificially, as with sodas.

• Simple, fast method.

• Used for entry-level wines.

• More aggressive and ephemeral bubbles.

Quick comparison

Conclusion

There's more to sparkling wines than champagne. Behind each bubble lies a winemaking technique and a style in its own right. Whether you're a fan of finesse or fruity freshness, there's sure to be a sparkling wine to suit you.

And for optimal tasting, remember to store your bottles in a La Sommelière wine cellar: your wines will be served at the ideal temperature for the bubbles to reveal all their elegance.