What is the method of sparkling wine making in which the wine undergoes fermentation in the bottle, with the remaining fermentation taking place in the bottle?

The traditional method of sparkling wine making that involves fermentation in the bottle is called the méthode traditionnelle, resulting in naturally produced CO₂ that carbonates the wine.

Explanation:

The method of sparkling wine making where the wine undergoing fermentation is bottled, and the remaining fermentation takes place in the bottle, is known as the traditional method or "méthode traditionnelle." During this process, yeast is added to the wine in the bottle, which ferments the sugars present and produces alcohol and carbon dioxide (CO₂). This CO₂ is dissolved in the wine under pressure within the sealed bottle, which results in the characteristic bubbles when the bottle is opened. The fermentation equation that takes place is C₆H₁₂O₆ (aq) → 2 C₂H₅OH(aq) + 2 CO₂ (aq).

Most fine sparkling wines and champagnes are created using this traditional fermentation method, wherein the CO₂ is naturally produced as a byproduct of fermentation. This is in contrast to less-expensive sparkling wines, where CO₂ is added to the wine under high pressure, similar to how sodas are carbonated. The naturally fermented sparkling wines typically have more complexity and are valued higher than those carbonated by direct CO₂ injection.