How Champagne Ferments: La Méthod Champenoise
When you pop open a bottle of champagne, the first thing you look for are the bubbles. They have an interesting appeal to our senses, and without them, the experience of drinking champagne just wouldn't be the same. There's a scientifically intricate method to making the bubbles. It's known as the "la Méthode Champenoise," or the Champagne Method. This process involves fermenting, blending and refermenting, bottling, riddling and dosage.
All wines are fermented. Fermentation is the chemical breakdown of the sugars in the grape juice, creating alcohol and turning it into wine. In the case of making champagne, it all starts with picking grapes by hand from a well-manicured and maintained vineyard. After the best grapes have been individually selected, they're pressed by barefoot grape-crushers to extract all the juice. Machines can't be used to press grapes producing champagne.
Once all the juice is collected, it's placed in stainless steel vats, where it rests until it becomes a still wine. This is the first of two fermentation periods. The next step is blending, which winemakers consider to be the most integral part of the Méthode Champenoise.
Choosing red wines from champagne villages, and adding them to the fermented batch falls on the hands of cellar masters. Cellar masters are professional wine handlers who have studied and worked with grapes and wines, and understand the process of making wine and champagne. The art of blending, or selecting the cuvée -- a blend of different wines that will result in the final champagne -- requires the ability to taste and determine the appropriate color, smell and taste. Every cellar master and village produces a unique and novel wine based on specific blending practices and recipes.
The bubbles are created during the second fermentation process. Sugar and yeast are added to the wine, which is then stored in a cooler setting, about 50 to 60 degrees Fahrenheit (10 to 15 degrees Celsius). This process -- which can take up to a few months -- can take place in stainless-steel tanks or in the bottles themselves. The wine ferments slowly, allowing it to mature through the aging of the fruity aromas of the grapes and release of yeast. This additional activity in the bottle produces alcohol and carbon dioxide.
During the fermenting process, sediment will settle out of the wine. Champagne fermented in bottles is slowly turned upside down; workers remove the cork and the carbon dioxide pressure blows out the sediment. Then the wine manufacturer may sweeten the wine by adding a little syrup that has been mixed with an older champagne.