After second fermentation, the added sugar has almost entirely disappeared, leaving the yeasts to finish their work. Enriched by their long weeks in the cellars, the yeasts now impart the nutrients they have absorbed to the wine, releasing the by-products of fermentation in the process.
Autolysis commences within three months of the end of second fermentation. The yeast cells gradually die and decompose, forming the lees that slowly enrich the wine with amino acids, proteins and volatile constituents. They also give the wine its complexity and add finesse to the bubbles. This is a time for patience, when the wine slowly awakens having become enriched with aromas and flavours over the course of its many weeks in the cellars. Autolysis is one of the fundamental processes in the making of Champagne, as specific to the Méthode Champenoise as pressing and blending. It is this combination of techniques and skills that ensures the consistent quality of Champagne wines. Hence the importance of the work carried out, for instance, by the AVC ((Association Viticole Champenoise) to further our understanding of Champagne making.
The rules governing the Champagne Appellation stipulate a minimum cellaring period for Champagne before release. This ranges from 15 months for non-vintage wines to three years from the date of bottling, for vintage wines. Final AOC certification is subject to the approval of the Institut National des Appellations d’Origine following analysis and tasting.
Le Travail de la Vigne: Aging
In practice, most winemakers leave their wines to age for much longer than the minimum periods required by law. How long depends on the type of blend —Pinot Meunier ages more quickly than your crisper Chardonnay — and the style of wine that the winemaker has in mind.
These generalities aside, every House boasts its own secret routes to success. Some of the bigger Houses, for instance, possess stocks of venerable vintages, stacked sur lattes (on their sides), that are only disgorged at the very last moment.