Second Fermentation in Bottle
Traditional method sparkling wines go through two fermentations. The first fermentation, which is usually carried out in tank (but could be in cask) creates the base still wine. After that the base still wines are blended ( a process known as the assemblage), according to the style and quality requirements of each producer, and the blended wine is put into bottle along with a mixture of yeast and sugar (called the liqueur de tirage) and then closed with a crown cap.
The bottles are then placed on their side in a cellar environment (about 50-52 degrees Fahrenheit). The yeast and sugar kick-start a second fermentation inside the bottle, in which additional alcohol (circa 1-2%) and CO2 are created. As the CO2 cannot escape it is trapped as bubbles in the wine.
Resting 'sur-lie' - Autolysis
After the second fermentation is complete the wines are left 'sur lie' (i.e. resting on its lees - the dead yeast cells in each bottle) for anything from 9 months to several years. Champagne, Cava and many other old world traditional sparkling wine appellations have minimum 'sur-lie' aging requirements. For example in Champagne it is 15 months for non-vintage Champagne, but in reality most Champagne producers leave their non-vintage wines resting 'sur lie' for up to three years.
During this time the proteins, amino acids and other compounds in the dead yeast cells are released and break down. This process is called autolysis and adds complexity to the wines such as the toasty/brioche/freshly baked bread aromas that one associates with Champagne and good sparkling wines.
Riddling, Disgorging and Dosage
As no Champagne or Sparkling wine consumer wants to drink a cloudy wine, the next steps are called remuage and disgorgement, i.e. getting the lees out of each bottle. The bottles are carefully riddled daily to slowly and homogeneously move the sediment toward the neck of the bottle (this is remuage / riddling). This process was traditionally carried out by hand but today is automated for efficiency. Once the sediment is neatly collected in the neck of the bottle, it has to be 'disgorged'. This is done by freezing the neck of the bottle in a bath of freezing brine.
Once frozen, the crown camp is removed and the frozen ball of lees sediment shoots out, after which the bottle is quickly topped up with a mixture called the 'liqueur d'expédition or 'dosage' - i.e. a mixture of wine and sugar, based on the eventual style of the wine. For example 'Brut' style contains between 6g and 15g/l of sugar.
Once the liqueur d'expédition is added the bottle is closed with the requisite Champagne cork, wire muzzle and foil and prepared for release. Though the wines usually rest and additional six or more months so that the dosage is fully integrated before being sold.
EU ruling banning universal use of term 'Champagne Method'
This method of producing sparkling wine was originally called the 'Champagne Method,' until a group of Champagne producers successfully lobbied the EU against its use by non-Champagne producers. As a result traditional method sparkling wines sold in the EU cannot use the term Champagne Method - instead they use 'Traditional Method' or 'méthode traditionelle'. This EU ruling has largely been accepted by sparkling wine producers globally, though you do occasionally still see "Champagne Method' on some sparkling wines made and sold in the United States.
Mary Gorman-McAdams, MW (Master of Wine), is a New York based wine educator, freelance writer and consultant.
Previous Wine Words
• Wine Words: Clarity
• Wine Words: Color
• Wine Words: Complexity
• Wine Words: Texture
• Wine Words: Aromas
• Wine Words: Alcohol
• Wine Words: Body
• Wine Words: Tannin
• Wine Words: Acidity
• Wine Words: Minerality
• Wine Words: Length and Finish
• Wine Words: Sweetness
• Wine Words: Style
• Wine Words: Oak
• Wine Words: Clarity
• Wine Words: Extraction
• Wine Words: Sediment
• Wine Words: Variety vs. Varietal
• Wine Words: Reserva, Riserva, Reserve
• Wine Words: Quality
• Wine Words: Vintage
• Wine Words: Non-Vintage
• Bordeaux Blend
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