At a temp where it first starts to freeze, only a little bit of it freezes since more water than ethanol solidifies, raising the ethanol concentration in the remaining liquid. So, it just gets a little bit of slush. As you lower the temperature, it gets a little more slush.
-Al
So here’s another data point. Just had a case of wine delivered from CA via FedEx. They were packed in a cardboard box with the egg crate type packing inside. The temps along the way have been below zero for the last several nights and only single digit highs during the day. It was 15 below last night in Denver where they sat before hitting my dock today.
Completely liquid. No cork movement, still see depressions. The bottles are very cold to the touch, but nothing else seems wrong and this after below zero exposure for at least 2 nights.
I f’d up, wasn’t paying attention to the weather, and have 3 bottles of burgundy en route via ground. Was to be delived today via UPS. Exception. Now to be delivered Monday after sitting on a trailer, outside, all weekend with nightime temperatures at -10 F. Will let you know.
It isn’t the outside temperature alone that matters. It’s how long it takes for the low temperature to settle on the liquid inside the bottle, and how long it stays at that temperature. The science that Alan brought out may be clear, but the storage variables aren’t always clear.
We say that a case of wine sat for days at below zero, but do we know what the temperature inside the box reached? Do we know how much other material surrounded that box making a kind of protection barrier? Do we know if the truck was warmed or not?
Again, anyone wanting to take the risk–go ahead. It’s your choice. But having seen what can–and does–happen, it would be irresponsible of me to recommend taking the risk.
Incidentally, I feel for the Mountain States right now and do hope that system does not make it to the Finger Lakes. Considering where I live, this may sound strange, but I hate winter!
Thomas. The variables you mention are, of course, part of the calculation. Wine freezes at a certain temperature based on Alan’s formulae, and Al is of course correct as the water freezes first, that increases the concentration of the remainder and makes it that much harder to freeze. But, of course, duration matters. And (of course) the duration calculation changes based on the heat permeable nature of the container. And (of course) the duration calculation changes based on the starting point (warmer bottle to start, warmer air mass surrounding the bottle in the container). So, to do this properly, you’d need the starting temp for the wine in the bottle, the temp of the air surrounding the bottle (inside the packing), a formula for the heat exchange of the packaging, the outside temperature, and the duration of exposure to either a constant or changing outside temperature. Did i miss any?
Peter, you missed the ABV of the wine and the I.Q. of the guy who packed it, as well as the truck driver’s stopover habits.
I’ll also let you know. I have a 6 pack of Coche that was failed to be delivered yesterday. So after sitting out at bout 5 degrees last night we’ll see the condition. By the way does wind chill affect these calculations ?
If it’s 26F and the wind chill is 10F, the wine (normal abv) won’t freeze, because it’s the actual temperature of the wine that matters and it won’t drop below 26F. But if the air temperature is below the freezing temperature of the wine, the wind can matter because it increases the rate at which objects equilibrate to the ambient temperature. The way an object cools is by giving up heat to the cooler air, the wind then carries away the slightly warmed air and replaces it with cold air. If the wine is in a truck, the wind will help the air inside the truck to cool because it forces cold air through cracks, etc. Bascially, wind chill doesn’t change the temperature a passive object will ultimately reach, it just increases the rate that the object cools to the ambient temperature.
-Al
Yep, definitely have got to know the truck driver’s stopover habits…
Al has described things perfectly. Just another comment to clarify confusion that I find people often have: wind chill is something that really applies only to living things, which, in addition to the absolute temperature around them, can also loose energy (and thus become cooler) through evaporation. You feel wind chill because you have skin and perspiration that can evaporate, and in so doing extract energy from your body. Inanimate objects can’t do that (unless they have water that can evaporate, such as a wet sponge or towel).
Love this thread, love SCIENCE!!!
All this debate can be easily settled with a scientific test using an environmental chamber like this Tenney Jr:
I used the larger size (which would be perfect for studying the insulating properties of styro vs cardboard shippers) years ago in the aerospace industry. Very accurate.
Results not so good. Houston, we have a problem....... - WINE TALK - WineBerserkers
Yeah, sad, but as you would expect for sub-zero temp for an extended period. Sorry about that. I had a few bottles ship across country this week, haven’t been to my locker to check on them, keeping my fingers crossed.
Another thing to consider is the latent heat of freezing, for water it’s about 80 times greater than the specific heat. In other words it requires 80 times more heat loss to freeze a bottle than to cool it by 1°F.