[pinetree]

My son bought be a thermostat that I can plug a freezer into; that is, it'll ct off power to the freezer when the set remperature is reached.

Well, somehow the capillary slipped out of the freezer and now my English Pale Ale is frozen in the carboy (secondary).

This is the third week of fermentation, but it's probably not complete.

Will this come back to life once it reaches the original set temp of 60 degrees F?

Thanks.

Greg

[tubercle]

Probably.

 Wild yeast have survived millions of years in freezing tempratures. There will be some damage to the yeast but after 3 weeks, unless it is very high gravity, most of the ferment is complete. Should be about ready to bottle or keg.

 Don't worry about it. Enjoy.

[tschmidlin]

You'll lose about 90% of the yeast when you freeze it like that, if not more.  They are already in a less than ideal environment (acidic, alcoholic) and given the speed of freezing they won't have much time to prepare themselves to freeze.  Normally temperatures drop over longer periods of time than going from ~60 to <32 as fast as a freezer will pull the temp down, and the yeast will create trehalose and other cryoprotectants to allow them to survive freezing better.  There are other genetic factors and environmental conditions as well, but the domesticated brewing strains are not selected for their ability to survive freezing.

So tubercle is totally right about wild yeast, but we're not talking about that.

He's also right that after three weeks the beer should be finished anyway.  Check it when it thaws, and if it's not done you will probably want to warm it up further and add some fresh yeast.  I'm sure it will be fine though.

[pinetree]

Thanks. It's thawing now.

Good shout about pitching more yeast.

[Jimmy K]

Its probably not entirely frozen of the expanding ice would have broken the carboy. And hopefully after three weeks the beer was just conditioning and not actually fermenting.

[Kit B]

I'd definitely be worried about the integrity of the carboy.
If you are using glass, please be cautious.
I'd recommend letting it sit where it is & siphoning or pumping it to a keg or bottling bucket, before moving the carboy.
A friend of mine recently had a temperature change create a crack in a carboy that he didn't see.
As he lifted the carboy, it shattered in his hands, nearly severing his thumb.
He'll carry a nasty 3" reminder (scar), for probably the rest of his life.

[James Lorden]

Just a thought.  Ice crystals can be very damaging to cell walls which is why a frozen then thawed piece of meat will expel so much liquid.  With a yeast cell I wonder if this type of damage could ultimatly lend itself to autolysis flavors.