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Salt lowers the freezing point of water thus allowing it to get colder w/o freezing

the fact that the salt melting the ice helps isn't surprising. the mythbusters guys did an episode on this sort of the thing - and ice water (instead of just ice) was the quickest thing to cool off cans (or bottles, i forget) of beer. (well, dry ice was quicker i think, but anyway)...

not that i'm disagreeing with the salt thing - but if you don't have salt or something, then throw some cold water in the ice and that will help as well!

Sort of, only it's got nothing to do with the ice molding to the bottle.

When you add salt to ice, the freezing point of the ice is lowered. That reaction requires a heat source (the bottle of relatively warm wine). By drawing the heat out of the bottle of wine, the wine is cooled.

It's exactly like using salt and ice to freeze ice cream.

TDS7,
Almost. Lots of things will lower the freezing point of water (e.g. alcohol or sugar), but plain old water isn't one of them.

Both are true---an ice/water slurry does increase the contact area with the bottle assisting in heat transfer and salt lowers the temperature which is great if you ever need to keep ice cream frozen in a cooler. If I want quick results I usually add both water and salt, why wait for the salt to melt the ice?

lets fight about it!

I learned this on Mythbusters. I usually do it in the sink. I too add water to my ice. It really does work really fast.

water works, not because it lowers the temperature (it doesn't), but because it increases the surface area of cold stuff touching the bottle.

If you keep the water/ice moving, it will cool even faster, because it will move the warm liquid away from the bottle and replace it with cold water.

I saw this tip via Harold McGee (his blog, maybe? or the NY Times?); the salt lowers the freezing point of the water. He did offer the caveat that since the water is super-cooled, it will very easily damage your skin (as in freezerburn). I haven't had an occasion to try it yet, but it's in the memory banks!

http://www.abreadaday.com

Oh my. Salt water does have a lower freezing point than pure water, as has been pointed out. The salty ice will then start to melt without changing temperature. Melting is a phase transition from solid to liquid, and it needs energy. The warm bottle of wine provides energy. With or without salt, ice will go from a solid at 32 F to a liquid at 32 F, and then the liquid starts to heat up. Obvious, this doesn't happen to the whole ice cube at once, but the laws of physics are such that every solid must go through this phase transition to liquid before heating. So, when you lower the melting point by adding salt, the ice goes from solid at 32 F to liquid at 32 F and stays at 32 F because more available energy goes into the melting transition than into heating the water.

The whole system will eventually stabilize at some temperature in between the wine starting temperature and the salty ice starting temperature (depending on the relative volume and therefore heat content of ice and wine) whether you add salt or not. What changes with salt is the rate of cooling.

I don't care what y'all say.........I KNOW IT'S MAGIC!