A tasting event featuring grower Champagne’s from the Terry Thiese portfolio this week started me thinking about what makes Champagne special . . . besides the bubbles. One element that sets it apart from many other (but not all) white wines is a dependence on aging sur lie (say sir-LEE), a French phrase that refers to the technique of leaving wine to mature on its fine lees, which are themselves nothing more than the very fine husks of dead yeast cells left after fermentation is complete.
To age sur lie involves leaving the wine in contact with a layer of this creamy white sediment for a period of time. Typically, it just lies at the bottom of the tank, vat, or barrel, but sometimes it’s purposely stirred up. Leaving wine in contact with its lees is traditional in Muscadet, where the technique adds body, breadth, yeastiness, and complexity (leesiness?) to the rather neutral melon de Bourgogne grape. It also has an important role to play in the making of white Burgundy where lees are periodically stirred up with a baton in an attempt to enhance their influence on the wine. The practice is called, sensibly enough, battonage (bah-tun-AHJ).
In the production of sparkling wine, lees appear in the bottle rather than a vat or tank, as a result of the second, in-bottle fermentation that makes the bubbles. Having the wine rest on these lees in the bottle is so important to the finished product that the time involved is usually set by law.
This is the case with Champagne (15 months on lees for non-vintage blends; 36 months for vintage),Spanish Cava (9 months) and Italian Franciacorta (24 – 60 months) and can be used, though is not required, for the making of Prosecco. As you likely know, the problem of how to get those yeast cells out of the bottle before it gets to a consumer has resulted in the complex processes of riddling and disgorgement whereby those dead cells are induced to collect in the neck of the bottle by tipping its bottom progressively upward in a rack made for the purpose. When the crown cap is popped off, the pressure inside the bottle pops the plug of dirt out and the wine that remains is clear of any debris.
Time on lees has an added benefit for bubblies. Enzymes are spawned that consume yeast cells in a process called autolysis — it’s this reaction that gives Champagne and other quality sparkling wine a good deal of the special character we associate with them. Tom Stevenson refers to this character as Champagney — an expression which, though self-referential, may get as close to describing the effect as one can get.
Yours sur lie,
–stephen