Frédéric Engerer and the technical team meet regularly from mid-January onwards to taste the wines from all the plots and the selections that were made at the vinification stage in collaboration with Jacques and Eric Boissenot. A wide range of wines is analysed to determine the best blend that will be used to make Château Latour. The blend is then decided for Les Forts de Latour and finally for the Pauillac. It is also at this point that some of the press wines are reincorporated, depending on their quality and the vintage's overall balance. The wine is matured uniquely in French oak barrels from the forests of Allier and Nièvre. The barrels are renewed every year for the Grand Vin. The wine stays in the barrel cellar for the first year until the beginning of the summer following the harvest. Rather than being hermetically sealed, the barrels are loosely stopped with a glass bung to facilitate a very slow exchange of gases between the wine and the atmosphere. The level of the wine in the barrel gradually goes down due to absorption by the wood and evaporation; the barrels are topped up twice a week in an operation called "ouillage". Before the arrival of the summer heat, the barrels are taken down to the second year cellar for a further maturing period of ten to thirteen months. There the wine can continue to age in hermetically sealed barrels (placed with the bungs on the side) protected from any variations in temperature. A year after it has been put in barrels, the wine is clarified using egg white (four to six egg whites per barrel). This very old technique enables any particles still in suspension in the wine to be drawn down to the bottom of the barrel and removed. A final racking about 45 days after this fining separates the bright, clear wine from the lees. The wine is tasted to determine when it should be bottled: it has to have lost the generous vigour of its early youth while retaining its finesse and substance, but should not have begun to "dry out" (a deterioration in the wine which is caused by too much time in the barrel).