Designation for a very long-stored (20 to 50 years and longer) and high-quality wine used in the production of champagne, usually from a single vintage. It is partly stored in large magnum bottles, stainless steel tanks or also in barrels. At the Champagne house Bollinger, for example, it is stored in magnum bottles to which a tiny amount of sugar and yeasts have been added to create effervescence(pétillance = bubbles). It gives the champagne the unmistakable character of a house. It is or can be added at three points during production, namely during the assemblage (the blending of different wines or vintages) as well as during the two types of dosage (filling dosage and shipping dosage).
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