Muscadet Cotes de Grandlieu Sur Lie wines are produced under the Muscadet Cotes de Grandlieu appellation of the western Loire Valley in France. They are produced from Melon de Bourgogne grapes, grown specifically in vineyards around the Lac de Grand Lieu (after which the appellation is named), just to the south-west of Nantes.
Melon de Bourgogne is not a particularly flavorful grape variety so without care in the vineyard and attentive winemaking, Muscadet wines can risk being rather bland and featureless. This is emphasized by the fact that the western Loire has one of the wettest, coldest growing seasons in France, and the grapes can struggle to achieve full ripeness and flavor development. To counter this, local vignerons traditionally retained a portion of their wines for personal consumption and left them sur lie ('on the lees') over the winter. With a more complex flavor and creamier mouthfeel, the resulting wine consistently increased in popularity over the years until it was eventually legally recognized as a distinct style of Muscadet wine. The wines of all four Muscadet appellations are now made in both standard and sur lie variants.
To legally earn the title Sur Lie, a Muscadet wine must be aged sur lie (either in tank or barrel) from the point of vinification until March of the following year. They must not, however, spend more than one winter on the lees.
A good Muscadet Cotes de Grand Lieu Sur Lie wine has a creamier mouthfeel than standard Muscadet – the result of the extended lees contact. In terms of flavor, it has subtle apple and citrus aromas, sometimes dressed with gentle hints of pepper and even a slight salinity evocative of the Nantais' maritime location. The best examples also have a certain underlying minerality, often thought to be a reflection of the chalky soils that characterize the best Muscadet vineyards.