Wines, specifically red wines, develop certain characteristics during the aging process: Bouquet, which is the smell; and taste. The older the wine, the lesser the need for breathing, or oxidation (adding oxygen in exchange for electrons). Wine actually goes through a very slow oxidation process in the bottle. So, the younger the wine, the more breathing it requires. A very young wine needs to breathe for several hours before consumption, while an older wine needs perhaps one hour. In fact, if a very old wine breathes too long it can lose some of its important characteristics. In some instances, breathing alone will not be enough, and the wine has to be decanted, or poured into a different recepticle. The act of decanting wine (usually only necessary in very young wines) aerates the wine and releases aromas and flavors.
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