When all the grapes have been picked, when fermentations are over and the last grapes have been pressed, silence finally returns to the cellar. Some tanks are doing malolactic fermentation, a second “fermentation” carried out by bacteria, in which malic acid is converted into lactic acid (Read our article: How is my malo doing?) https://www.vinparleur.net/malolactic-fermentation-in-wine?), while others are already blended and prepared for winter. Its time to fill up tanks and barrels and having a final tasting of the cellar to appreciate the job.
While the wines seem to be sleeping during the following months, they are nevertheless undergoing a profound and essential change. Due to gravity, the wines become clearer, as yeasts, proteins and other macromolecules sink down to the bottom of the tanks, forming the lees. Tannins combine and become smoother, the color of the red wines stabilizes, aromas are shaped and changed creating the bouquet. This period of harmonization may be more or less long, depending on the character of the wine, grape variety and quality, soil and terroir and the choice of the wine makers. For Primeur wines, simply structured and marked by fermentation aromas, it takes only a few weeks, while it may need months or even years for more complex wines.
Development of the wines is mainly followed by tastings, while some important parameters are checked in the laboratory. Taste and aromatic development decides among other things when and how often the wines are racked and separated from the lees. The latter is indeed an interesting source for aromas and taste, but in the case of strong reduction, it may also be a source for unpleasant odours in the wine.