Accidentally froze yeast slurry, salvageable?

[gravrain]

So after making some of EdWort's Apfelwein I grabbed the yeast slurry for making a batch of cranberry Skeeter Pee. I tossed the bell jar I put the slurry in into a new kegerator I had just inherited and turned on. Apparently it was waaay too cold and the yeast slurry froze. I have transferred it to the main fridge for it to warm up slowly hoping that some of the slurry is salvageable.
Just wondering if anyone knew if a pretty thick slurry of yeast could survive a night and day of being frozen.

Thanks.

 

[djsethall]

There has to be some viable cells left, why not throw it into a starter and rejuvinate it a bit, then rewash? You will have perfrctly pitchable yeast after that

 

[LakewoodBrew]

It's probably fine, just let it thaw out slowly. Pitching a starter woudn't hurt either.

 

[dwarven_stout]

There has to be some viable cells left, why not throw it into a starter and rejuvinate it a bit, then rewash? You will have perfrctly pitchable yeast after that

My thoughts exactly.

 

[gravrain]

Awesome, I'll gently bring it to pitching temp and see if anything takes. If anything cool happens I'll let y'all know.

Thanks.

 

[Saccharomyces]

As the yeast freeze, ice crystals form that pierce the cell walls. As it warms up the now dead cells will leak out their contents, releasing enzymes which will cause any cells that survive to cease fermentation. In short, it's toast. Toss it, do another batch of cider as a new starter and try again... you'll be making more cider anyway, no doubt.

 

[djsethall]

As the yeast freeze, ice crystals form that pierce the cell walls. As it warms up the now dead cells will leak out their contents, releasing enzymes which will cause any cells that survive to cease fermentation. In short, it's toast. Toss it, do another batch of cider as a new starter and try again... you'll be making more cider anyway, no doubt.

If I am hearing this correctly, there is absolutely no chance of being able to save the starter? You couldn't do a step up with a wash in between each step and end up with viable yeast?

 

[oldmate]

Actually, you can stop the ice splintering effect by re-heating as quickly as possible. For meat, it's by microwave. Yeast is going to be dead either way.

 

[emjay]

In all likelihood, it's no longer any good. But, if it were me, I would try making a fresh starter with it and seeing if it ferments, and perhaps even stepping it up and making another starter with that yeast, if the first was somehow successful.

Then again, I currently have two 5-gal buckets containing a combined 25kg (55lbs) of DME, so I don't mind wasting some