Designation for a very long-stored (20 to 50 years and longer) and high-quality wine that is used in the production of champagne and usually comes from a single vintage. It is sometimes stored in large magnum bottles, stainless steel tanks or barrels. At the champagne house Bollinger, for example, it is stored in magnum bottles to which a tiny amount of sugar and yeast has 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 assemblage (the blending of different wines or vintages) and during dosage (bottling and despatch dosage).
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Thomas Götz
Weinberater, Weinblogger und Journalist; Schwendi