Lees

Residual particulates, predominantly dead yeast cells, that are present after the primary fermentation in winemaking. It is used most often in reference to the traditional Champagne method of producing sparkling wines in which the wine is aged in bottle on these remnants during the secondary, carbonating fermentation, referred to as "Sur Lie". It is also occasionally used for white wines in which the wine is similarly aged on these yeasts to impart greater complexity to the wine. Overall, lees aging typically gives a more yeasty profile to a wine, giving aromas and flavors of bread or pastries, nuttiness, and an overall deeper complexity.