During the ageing of the wines in barrel, the regular rackings clear the wine, but their long-term stability is only acquired after a rather colourful but nevertheless very effective operation -the fining.

Its principle, which has been known for many years but only applied to great wines from the 17th century onwards, lies in the ability of egg white proteins to react with the tannins in red wine. This phenomenon brings about the sedimentation in the form of lees of a certain number of unstable components which could possibly make the wine cloudy once in bottle.

Generally, five or six egg whites are used per barrel. They are lightly whisked but not stiffly beaten, and then poured through the bung-hole into the barrel. The wine is then stirred vigorously to make sure the egg white mixes quickly and evenly with the wine. The barrels are then turned so that the bung faces the side and comes into contact with the wine, and are left for a month and a half. They are then racked, i.e. decanted carefully.

Apart from being an elaborate form of clarification, fining leads to a noticeable development of certain characters in the wine. The aromas become finer and more complex, the tannins less harsh, the body more tender, the finish softer. Sometimes this development is the subject of criticism -as if looking for finesse were a sign of weakness, as if to be powerful, the wine had to be aggressive.