It takes no more than one hour for grapes picked at Château d'Yquem to arrive at the cellar. Pressing takes into account the texture and fragility of the fruit.
The grapes are pressed three or four times at Yquem. As opposed to other white wines, the sugar content and quality increase with each pressing. The first pressing in a pneumatic winepress produces 75% of the total juice, with about 19° potential alcohol. The second yields 15% of the total juice, with about 21° potential alcohol, while the third can reach up to 25°. The hard cake of pomace is then broken up, destemmed, and put through a low-capacity vertical press. If the harvest is very small, we use these same vertical presses exclusively, without recourse to pneumatic presses. Wines from the various pressings are blended before barrel fermentation.
Unusually in Sauternes, fermentation at Yquem takes place in barrel to maintain maximum control over this most delicate and mysterious part of winemaking. Only new barrels are used each year. These are made with the finest stave oak from forests in the eastern part of central France. Each individual barrel is closely monitored, and the château's in-house laboratory carries out regular analyses. The most active musts finish fermenting in just two weeks. However, others can take up to six weeks. Fermentation stops naturally in all instances. The alcohol content at Château d'Yquem varies from 12.5° to 14.5° according to the sugar content of the must. The ideal figure is 13.5° with 120 to 150 g/l of residual sugar.