For our Bubbles and Bivalves event on New Years Eve we poured the Adami Sur Lie Prosecco and I fielded several questions from staff and guests about the significance of sur lie. For anyone who didn’t get an explanation and would like one I offer the following . . .
Sur lie is a French phrase that describes the technique of leaving wine to age on its fine lees – mainly dead yeast cells. This means that once fermentation is complete, the wine remains in contact with a layer of a creamy white sediment for a period of time, and is not racked or filtered before bottling. Typically, it just lies at the bottom of the tank, vat, or barrel.
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 a role in the making of white Burgundy where lees may be periodically stirred in a practice called battonage to enhance the effect. Reds may also be aged sur lie.
In the production of sparkling wine, time on the lees is so important to the finished product that it may be a legal requirement. This is the case with Champagne (15 months; 36 months for vintage), Cava (9 months) and Franciacorta (from 24 – 60 months) and can be used, though is not required, for Prosecco.
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 — which though self-referential may be about as descriptive as one can get with this.
Something called mannoproteins are also released by lees. These contribute to the creamy smooth texture of really fine bubbly.
Hope this is useful.
Yours sur lie,
-stephen