When Lees are utilized during the winemaking process it’s common to see “Sur Lie” on the label, meaning “on the lees”. You may have seen this on Champagne labels or maybe a white from the Loire Valley but what does it mean exactly? I mean, who is “Lee” and why is the wine on top of them?! In short, lees are dead yeast cells that have satiated their hunger for sugar and go into autolysis or self-destruction from certain enzymes created through fermentation (the process the yeasts initiate).
As the walls of the yeast cells are broken down via autolysis, small amounts of sugar and amino acid are released causing us to perceive a smoother and more structured wine. Apart from the mouthfeel/texture, the release of fatty acids contributes greatly to new and interesting flavors/aromas. Whenever I taste “Sur lie” it’s like someone dropped a knob of salted butter coated in fresh honeycomb and caramel but fished it out really quickly. Lees can offer a range of complex flavors and textures that change through the winemaking process; Lucious Enological ExpressionS (LEES!!).
It is worth mentioning that there are 2 different kinds of lees that occur in the winemaking process. There are “Gross Lees” which are post-fermentation sediment that falls to the bottom of the tank and is usually filtered out. Then, there are “Fine Lees”. These are the dead yeast cells that winemakers utilize to contribute to those interesting characteristics. It’s common to physically stir the lees to incorporate them more thoroughly into the wine (called bâtonnage “bat-on-naj” in French). Lees, while used predominantly for flavor/texture, can also protect wine from oxidation.
Fun Fact: By law, a non-vintage Champagne must be aged for 15 months in the bottle and spend at least 12 months on lees, according to the Comité Champagne.
What Do Lees Taste Like?
Champagnes from France are old-time friends of lees. Nuts like almonds/hazelnuts, bread, and hay are common aromas found in Champagne from lees aging. Flavors of freshly baked brioche, bread-like notes, and biscuits are also some characteristics lees help impart from the aging process. The autolysis process also gives champagne finesse and complexity in every bubble.
Other white wines contain similar aromas/flavors, like sparkling wine. However, when aged on the lees in oak barrels, you’ll notice flavors that the wood impart including “sweet, caramel-like notes, smoke-like flavors, clove flavors, and umami or meaty flavors of vanilla” (Wine Folly).
Classic wines that are aged on Lees:
(NOTE: Most red wines are usually racked off of their lees before aging begins, however, there are few winemakers that use lees in there red wines).
