Almost all wine served in North America is served at the wrong temperature, which impairs flavour and deprives the drinker of the full expression of its character.
White wines should be served cool, but not too cold. At 10-12°C (50-54°F) fruit and crispness are at their peak, but at colder temperatures, bouquet and flavour nuances begin to recede, and the wine goes numb.
Most restaurants hold their white wine in reach-in coolers, most of which also hold beer or soda, and they’re kept at 4°C (38°F). If your wine arrives as frosty as this, it’s perfectly acceptable to ask the waiter to let it warm up before serving it. If you’re not able to wait half hour, have them bring an ice bucket of warm water, and hold the wine for five minutes to take the chill off.
Red wines should be served at cool room temperature, but not warm. At roughly 18-20°C (65-68°F) fruit becomes more evident on the palate and in harmony with the tannins. Served too warm, red wines will seem “hot” (high in alcohol) and flabby, with poor fruit/tannin balance. If you are served a red wine at this temperature, go ahead and ask for an ice bucket—don’t be embarrassed or worried: if you’re paying for the wine you can do anything you want with it. Hold it in the bucket for five to ten minutes to take the edge off the heat and taste it. (Article courtesy of Tim Vandergrift, Technical Services Manager, Winexpert).