Homebrew Underground

In an earler post I wrote about keeping the fermenter cool during fermentation. In that example the fermenter was wrapped with a couple of wet towels. I also mentioned you could use a T-shirt instead of towels. Below is a shot of the fermenter in a tray of water using a T-shirt:

Using a T-shirt is a little more convenient because you can just slip the T-shirt over the fermenter (slipping the open end of the T-shirt from the bottom of the fermeneter). It will stay in place by itself. When using towels, I found I had to pin them together with safety pins to keep them from falling off the fermenter.

The T-shirt may be able to cool the fermenter more efficiently because it should be a tighter fit than the towels and the wet fabric will be in better contact with the fermenter. In theory, when water evaporates from the T-shirt, there should be better heat exchange with the fermenter. I haven’t been able to confirm this, though.

Don’t forget to fill the tray with ice. It will keep the fermenter cooler than when using only plain water. As the ice melts, the fabric will wick up the water.

By the way … that last batch of beer that was kept cool with the towels came out pretty good. I noticed one more benefit, too. When I transferred the beer from the fermenter to the carboy it was almost fully clarified. I think that was due to the fact that the beer took 7 days to ferment. In earlier batches when I didn’t keep the fermenter cool, the beer only took 4-5 days on average to ferment.