For great-tasting wine

Why is it that the same wine is terrific one time but lifeless the next? Most likely the bottles were
served at different temperatures.

Reds v Whites

To bring out their best qualities, tannic reds should be served at 59 to 64 degrees, just a few degrees above recommended wine cellar temperature. If they're served at a much warmer temperature, you'll most likely taste only the alcohol. However if they're too cold, you won't taste much of anything except the acidity. Lighter reds, like Beaujolais, are best served in the lower 50s to bring out their youthful fruitiness.

People have a tendency to pour white wine right after it's been taken out of the refrigerator, which robs it of its flavors. Full-bodied whites should be served somewhat warm, in the upper 50s (roughly cellar temperature). The higher its quality, the less cold white wine should be to bring out its flavors. Conversely, you can mask the faults of a mediocre wine by serving it as cold as a Martini.

Champagne is also frequently served too cold. British wine expert Hugh Johnson recommends serving it at the temperature of a deep cellar, "distinctly cool, perfectly refreshing, but not searingly cold in the throat like a can of lager straight out of the ice-box." Because dessert wines (Muscatels, Malagas, Marsala, and Madeiras) are strong and sweet, they should be served stone-cold.

Taking a Wine's Temperature

How do you know when it's the right temperature? Through trial and error: With whites, simply smell and taste the wine right after it's out of the fridge. Warm the glass a little with your hand and try it again. Do you notice how the flavors have emerged? With reds, do the opposite: Smell and taste a warm bottle, and then put it in the fridge for a few minutes. Now try it. Has it come back to life? (If it gets too cold, no problem; simply let it warm up some more.)

One sure way to gauge a wine's temperature is to buy a stick-on plastic strip thermometer-the type you put on a child's forehead. Just place it on the bottle, and you'll get an instant reading.

The simplest way to measure a wine's temperature is to feel the bottle with your hand and take a guess. With a little practice, you'll become an expert and won't need a thermometer at all.

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Room Temperature
The rule of thumb used to be "serve red wine at room temperature." This worked well back in the days when there was no central heating in the castles of Old Europe, and rooms were drafty and in the 50s. Today, "room temperature" can mean anywhere from the upper 60s to the lower 70s, clearly too warm for serving red wine.

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One "Scientific" Experiment
To determine how temperature can affect flavor, wine expert Lisa Shea assembled a panel to taste two affordable wines served side by side at different temperatures. They purchased four bottles of a 2001 Simi Sonoma County Sauvignon Blanc for the white, and four bottles of a 2000 Robert Mondavi Coastal Cabernet Sauvignon for the red.

Instead of "subtle, esoteric results," tasters found "bold, in-your-face, obvious results." Here are their conclusions:
Sauvignon Blanc
 - 72 degrees: What little flavor it had was "sharp and unpleasant."
 - 50 degrees: "Flavorful, crisp, tasty."
 - 44 degrees: "Little aroma, little flavor."
 - 38 degrees (out of the fridge for a few minutes): "Practically no flavor at all."

Cabernet Sauvignon
 - 72 degrees: "Very alcoholy."
 - 63 degrees: "This was great! Berries, black cherries, currants, oak."
 - 53 degrees: "The flavor was now dull with a sharp overtone, which wasn't very pleasant."
 - 45 degrees: "There was now no flavor at all, just a sharp taste."