Frozen WY1214

I was pulling my smack pack of 1214 to make my starter for this weekend, and the pack had been shoved to the back of the fridge in front of the vent, where it froze pretty hard.

Yeast manufacture was 5-Feb, and it could have been frozen for up to 2 weeks. The planned brew has a target OG of 1.052, so a starter may not have been strictly speaking necessary with a healthy smack pack. I presume it’s mandatory now if I want to salvage this pack. I figure nothing lost by thawing and smacking it.

So is it even worth trying to salvage this? or should I head to the not-very-local LHBS and look for a replacement?

Thaw, smack and if it balloons, use it. If it takes more than 24 hours to balloon, it’s probably dead.

Thawed, smacked, and after 6 hours there is some swelling; so apparently not completely dead, just mostly dead, which is slightly alive…

I actually have the grain for two batches; I was planning on harvesting the yeast from the first to make the second.

So I did go to the LHBS and got a vial of WLP500 anyway. ( $9.00 !!! ) So now I have the option to use the frozen smack for the first and save the new vial for the second, or ditch the frozen smack and use the new vial in both batches per the original plan.

Update for those who search the forum in the future with a similar problem.
I pitched the smack pack into the starter, and let it work for 24 hours. I did see the telltale frothing in the flask so there was definitely life there.

I pitched the whole starter without crashing into my 1.061 wort. (Decided to add extra sugar at the last minute) 16 hours later there is about 1/2 inch of fluffy krausen and good airlock activity.

So, while freezing liquid yeast is not good, it’s not a guaranteed fail either. Definitely do a starter both to replace the casualties and to prove viability. Definitely work a backup plan.

Freezing will cause approximately 10% loss of viability for each freeze/thaw cycle. Enter the production date into the yeast starter calculator and deduct 10% from the calculators estimate of remaining viability. Since your yeast was not moved around there was only one cycle.

Good to know. I was actually thinking it would be 50% or worse.

I really like starters, I’ve actually never made a beer using liquid yeast without one. Lately when I drop by my LHBS, he keeps expired packs and vials. I have made 4 beers to date using expired yeast.
One was a year expired, all made with a qrt starter. This was just a test, as I mostly buy new. The beers were all successes, and they all took off very well and finished like normal. It’s given me a new perspective about liquid yeast.

That’s good to know Old Guy, I think I’ll keep my eyes peeled for some specific yeast strains. Fresh is best I know, but if I need something and all I can find is old, I do know how to spin it on a stirplate.