THE QUESTION: How long can an open bottle of wine last in the fridge?
THE ANSWER: Generally no more than three or four days, but it depends on the wine style, the fluid level and your taste preferences.
Your chilling instincts are wise. All wine survives longer in the fridge. The reaction with oxygen, which initially benefits flavour but eventually causes an ignominious decline, decelerates at lower temperatures. I'm assuming you've replugged the bottle with the cork or some other stopper, which is crucial in preventing more air – or, worse, stale Chinese takeout odours – from turning your wine into ghastly swill.
Red wines, which contain protective tannins, tend to fare better than whites over time. Fuller-bodied, heavily tannic reds such as cabernet sauvignon last the longest, while light reds such as Beaujolais can fall apart more quickly, losing their fruitiness and taking on a bruised, sherry-like tang. Heavier reds can eventually acquire a port-like, prune quality, a flaw that some people (not me) enjoy. If you're dealing with a red, you'll want to remove it from the fridge an hour or so before serving.
Because oxygen is the culprit, bottles with more air between the fluid and the neck will decline more rapidly than fuller bottles. If your merlot or pinot grigio is less than half full, I wouldn't hang on to it for much more than two days. Unless, of course, there's nothing else in the house to drink, and you've had a hard day at work.
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