Cooling wort - snow/ice/outdoors?

[rskelhorn]

A couple weeks ago I wanted to cool wort outdoors because it was -35C and my deck has a good 3ft of snow on it. Took it out, stuck it in the snow and 10 mins later the wort was actually boiling! Read on the inter webs that snow can be an insulator.

This evening I'd like to brew again...

What is the difference in an ice bath and a "snow bath" ?

What if I fill a rubbermaid container with water, put my brew pot in it with a weight so it sits at the bottom and stick it outside for the water to freeze. Then pull the brew pot out and I'd have a perfect spot with loads of ice to stick the pot. Would this be any different than just sticking it in snow? If so, how?

Thanks!

 

[Cbaddad]

I think it would work better if it was not completely frozen yet. You want to have a way to move the ice cold water around the kettle so that it is constantlybeing exposed to the cold. Otherwise, it creates a blanket to some extent. Someone can more eloquently state the process, but I would just fill with a bit before. Stir the water in the container and if at all possible stir the wort gently as well. It will cool faster.

 

[Clonefan94]

Snow will insulate. When you plop the hot pot in the snow, it immediately melts and creates a layer of water that will actually reach equilibrium with the temp of the pot. The surrounding snow will kind of prevent it from cooling since it will trap that water there. The ice water bath has enough water and ice mixture to get a little convection current going and the water will be in motion, so the same temp water is not just sitting next to the pot. You need to get a nice mixture of ice (or snow) and water to make it more fluid than solid. It's all about being able to pull heat from the pot, move hot water away and let cold water re-enter that space next to the pot.

 

[balrog]

What these guys said; you can make it work but you have to keep it moving, either new snow to melt against the sides or move the pot around in the snowbank. I set my on a flat spot and use my feet to constantly pack up snow against the sides, it melts, I repack. It is not just set and forget. And frankly, it always works better for thermal exchange to have constant contact--like in a water bath filled with snow/ice into which the pot sits.

 

[JimRausch]

I regularly use a water/ice/snow bath to chill my 5G wort. 2 keys- 1.water does the cooling, the ice/snow keeps the water cold. So, use lots of cold water and add the snow/ice to it.
2. Change the water when it warms up. In my experience, I can get boiling wort down to pitching temp. in 30-45 minutes. I use a big swamp cooler bucket.

 

[Raygun]

If you can have it in a place where there's a tap or a faucet, just the slightest trickle of water (literally as light a stream as your faucet can put out) overflowing an ice bath will cool it amazingly quickly. This is the technique I use to chill warm beer.