How Cold Is Too Cold
A Chilling Limitation to Cold Temperature
By Mark Finch
Even though the groundhog didn’t see his shadow, it’s still that time of year when cold weather is the rule rather than the exception. And when cold weather rolls around it’s a great time to stay cozily inside, in front of the fireplace with a nice bottle of red wine or port.
Sometimes getting wine from the store to your home entails leaving it in your car for a period of time. So the question arises: Is my wine going to freeze? And then the second, more pertinent question: If it does freeze, does it matter?
Fortunately, the Department of Physics at the University of Illinois has given the first question some thought and even provided a handy chart. In a nutshell, the freezing point of wine depends upon its alcohol content and the presence of other components such as salts and sugars; for a typical wine with an alcohol content of 13.5 to 14 percent it’s going to be about 20°F. Ports, which are usually around 20 percent alcohol, won’t start to ice up until the temperature drops to about 15°F. A low-alcohol Riesling (say, 8.5 percent) will start turning into a slushy at about 25°F.
But does it matter? If a bottle freezes to the point that the cork is pushed out or the glass breaks, the answer is obviously yes. But if the contents are intact and the wine is allowed to thaw completely before opening, it should be just fine. Subjecting a wine to freezing temperature might promote the formation of tartrate crystals, but that shouldn’t affect the taste.
Excessive heat, on the other hand, will have a negative effect on wines — but that’s a topic for a summer newsletter. To be on the safe side, treat your wine as you would like to be treated — if you’re happy with the temperature, your wine probably will be too.