Yeast dead after crash cooling?

Hi all.
We made the Craig tube porter. We used US 04 yeast and after about two weeks we cooled it. Slowly dropping it a few degrees until about 5 degrees. We left it at 5 a bit too long i think. It was supposed to be 2 days but ended being about 4.

We bottled the brew. It's been 4 weeks now. We opened a bottle tonight and nothing. No carbonation.

Either the yeast died or fell out of suspension. It's winter here so it might be too cold for the yeast to carb maybe? Either that or we killed it during cooling. Any tips?

You've got it at room temperature now, right? Keep it at 20 C. or higher.

Yeast don't die at low temps, they just basically hybernate.

You are bottle conditioning at room temp, correct? What is the ambiant temp where you are bottle carbing/conditioning? If you are below 72F, your carb time might take longer. If you are below 60F or so, it is too cold to carb at all.

After a cold crash, yeast tend to be sluggish when you first bring them back up to room temp for bottling, but as long as there is sugar, they will reanimate and eat that sugar.

Worse comes to worse, you may need to open all the bottles, sprinkle a tiny bit of US-04 into each bottle, and recap.

Good luck!

Did you forget to add sugar before bottling?

I'm thinking OP's last paragraph is the important one. Ambient temp is important when carbing. It needs to be about 70f (about 20c) or higher to get a decent rate of carbonation. If you are cooler than that it will take a long time. If you are colder than about 15c, it may not carb at all.

freisste said:

I'm thinking OP's last paragraph is the important one. Ambient temp is important when carbing. It needs to be about 70f (about 20c) or higher to get a decent rate of carbonation. If you are cooler than that it will take a long time. If you are colder than about 15c, it may not carb at all.

Click to expand...

You're probably correct. I figured I'd ask about the priming sugar though. I've made that mistake before, along with probably 99% of HBT.

Another vote for either (a) the ambient temp is too cool, or (b) you didn't add (or mix) the priming sugar correctly (did you boil it or just dump in dru sugar?).

4 days at cold temps won't kill the yeast. 4 weeks at cold temps won't kill the yeast. They just go to sleep. Otherwise, how would people manage to culture starters from commercial beer bottles, hmmm?