Sparkling wine adds a festive air to any event, but the bubbles in Champagne have not always been a source of celebration. In the early production of wine in the Champagne region of France, the bubbles were considered a flaw and were causing some major problems.
The Champagne region is France’s northernmost wine region and has the coolest climate. The cool climate means that the grapes don’t always fully ripen, which results in tart flavors and high acid. The cool climate also affects the fermentation. Normally, fermentation will continue as long as there is sugar for the yeast to convert. However, if the temperature drops below 50°, the yeast will go dormant. The early vinters in Champagne would see that the yeast had stopped producing CO2 and mistakenly think that the fermentation had completed. The wine would be aged and bottled, but then, in the spring when the temperature rose, fermentation would begin again and create CO2 in the bottles. The bottles were not built to withstand the pressure and many would burst.
Eventually, the winemakers realized that the cold temperature was the root of the problem, so they moved the wine-making underground into the caves, where the temperature was more stable. Now the grapes could be fully fermented into a still, dry wine. However, the bubbles had become desirable, so the winemakers started to add a mixture of wine, sugar and yeast (liqueur de triage), to instigate a secondary fermentation to generate a controlled amount of bubbles and pressure.
At the end of secondary fermentation and while aging, the bottles are slowly rotated in a manner that forces the dead yeast cells to accumulate in the neck of the bottle. This process is known as remuage or riddling. Next is the dégorgement step, where the neck of the bottle is dipped into a solution that freezes and expels the yeast sediment. Finally, the bottle is topped up with a blend of wine and sugar (liqueur d’expedition). This final step is called dosage and determines the sweetness of the Champagne. These are the official levels of sweetness for Champagne:
Brut nature: 0-3 g/L
Extra Brut: 0-6 g/L
Brut: 0-12 g/L
Extra Dry: 12-17 g/L
Sec: 17-32 g/L
Demi-Sec: 32-50 g/L
Doux: 50+ g/L
This technique of secondary fermentation in the bottle has became know as méthode champenoise or méthode tradionnelle. To protect regional identity, only wines from the Champagne region in France can use the name Champagne or the term méthode champenoise on their labels. Sparkling wine from other regions in France is usually called Crémant and can list méthode tradionnelle when secondary fermentation is done in the bottle.