In any event, in my personal experience most of the effect lasts for about 12 to 24 hours at most. That's fine in most cases since an open bottle is often finished the next day. If you intend to keep an open bottle for several days, you will probably need to repeat the evacuation procedure each day. Most wines will weaken and lose intensity over this period using this method.
About the Expert:Roger has enjoyed a lengthy career in the wine trade, and he last served as a senior executive with a major national importer. In 2006, he launched Millesima USA, a retail entity affiliated with Europe's leading fine wine mail order company. Roger became one of America's first Masters of Wine in 1993, and he has been very active as an educator and speaker at wine festivals and conferences. He hosts a community television program entitled "Wine's Simple Pleasures," and is currently working on a book of original recipes and wine pairing solutions.
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