Will wrapping a bottle in a wet paper towel make it chill faster?

Take a couple paper towels and wrap them around your beer, then douse it in water. It should be soaked but not dripping (you don't want ice forming in your freezer). Air is not a very good heat-conductor. Water is a better conductor, plus you get a little boost from evaporation. Pop it in the freezer for 8-15 minutes, depending on the freezer's temperature (err on the side of caution).

Does this make the bottle chill faster in the freezer?

• "Can it be proven?" Err.. yes. By you, with two bottles, a wet paper towel, and 15 minutes. This will be tricky to answer, because who is going to do a peer-reviewed study that can be conducted so easily? Feb 7, 2014 at 4:10
• I think you'd get a better answer on physics.SE where they would also be able to explain the mechanism Feb 7, 2014 at 8:55
• A short warning: if you start regularly cooling your beverages in a freezer, sooner or later you will forget to take it out before it explodes. Trust me on this one. Feb 7, 2014 at 12:34
• The claim in fact says: "wrap it in a wet towel AND put it into the freezer". So what are we comparing to? A dry bottle in a freezer? A wrapped bottle on the table? It's almost like "I can show you how to make a bomb out of a paper roll and a stick of dynamite". Feb 7, 2014 at 14:31
• This is the same principle with cloth covered canteens. The water evaporates, taking heat from the bottle with it. Says the same thing
– user11643
Feb 8, 2014 at 19:02

I knew this would work theoretically, but I looked for people actually performing the experiment empirically.

To my surprise, I found a carefully performed experiment in a 2014 blog article that concluded:

BUSTED! Depending on how you wrap the paper towel it will either have no effect or slow down the cooling of your favorite drink.

Here is the killer diagram (referring to glasses, not bottles):

He shows that for pint glasses, the unwrapped version cooled faster, but for bottles there was no major difference.

However, the comments on the blog include people whose experiments agreed and disagreed, including a link to Physics.SE: Does wrapping a wet paper towel around a glass bottle really speed up the cooling process? where one person's experiment revealed the direct opposite:

[...]

So yes, the wet paper towel trick does seem to work quite nicely. I'd expect it to work even better if one were to use a ventilated freezer (faster heat exchange) and smaller containers (greater surface/volume ratio).

Obviously these are amateur non-peer-reviewed results, but in the absence of more serious research (I did look, but came up empty-handed), I am forced to say "It is still unclear."

(Meanwhile, in my head, I switch back and forth in my views. Maybe more contact with the cold walls of the refrigerator, by placing the bottles horizontally, would improve the effect of the water's thermal conductivity, but without that, it is just another layer of insulation between the air and the drink?)

• I think the accepted answer on the Physics SE question sheds some light on the variables that make this hard to determine a straight up best answer (see also how wildly the results of "Mpemba effect" vary depending on experimental caution). For example, is the damp cloth cooler than the liquid in the bottle? That's a huge difference right there. Freezer humidity is probably a huge factor, if it's very dry then you get evaporation cooling. It seems like neither of those experiments detail the controls enough to say why they are opposite conclusions.
– JMac
Mar 25, 2019 at 17:21