Frozen Yeast

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WildGingerBrewing

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My yeast froze!!!!! I have a smack pack of Wyeast Kolsch I was planning on using tomorrow. It's been in my freezer for a week and when I pulled it out to smack it this morning it was frozen. Is it still usable? Can I still smack it once it thaws?
 
Make a starter and see what happens. I'd have a backup yeast ready just in case though because I'd have to think there's a really good chance that it's toast.
 
My yeast froze!!!!! I have a smack pack of Wyeast Kolsch I was planning on using tomorrow. It's been in my freezer for a week and when I pulled it out to smack it this morning it was frozen. Is it still usable? Can I still smack it once it thaws?

Of course. That's the beauty of a smack pack.

I'd bet it still bloats (might take a little longer). Let us know how this turns out. Thanks.
 
I've gotta ask, what did you expect it to do in the freezer?

Well, obviously I wasn't thinking at all :D I bought it and just threw it in the freezer with the hops without even thinking about it being liquid. I use US-05 more than anything and always just throw it in the freezer. Of course it's usually only in there a day or so before I brew. I bought this last Friday! Oh well, live and learn.

As of now it's thawed and smacked. Hopefully in a few hours it will start to bloat. I figure if it expands, it's still good.

Thanks to everyone!
 
As of now it's thawed and smacked. Hopefully in a few hours it will start to bloat. I figure if it expands, it's still good.

It means that there were some cells still viable. I guarantee that many, if not most, of the cells were killed. If pitching the smack pack alone was underpitching, pitching it now will be doing so pretty severely. To put this in perspective, a properly rehydrated US-05 will have roughly 230 billion cells. The smack pack in perfect condition, fresh from the lab will have roughly 100 billion. How many are left now?
 
After giving it some thought, I just went and bought another smack pack. The thawed one didn't seem to be expanding and I didn't want to take any chance. So, never freeze your yeast!!!!!
 
Just put the yeast in your fridge. I store mine in there for weeks/months and they are always fine. I make starters now on my DIY stir plate (awesome build), but even when I didn't I just warmed them up a day before the brew and they were ready to go!

BTW - next time check with me as I usually have bottles of yeast ready to go and only live a short ways away from you :tank:
 
Just put the yeast in your fridge. I store mine in there for weeks/months and they are always fine. I make starters now on my DIY stir plate (awesome build), but even when I didn't I just warmed them up a day before the brew and they were ready to go!

BTW - next time check with me as I usually have bottles of yeast ready to go and only live a short ways away from you :tank:

Thanks. I appreciate that. I haven't made a starter before but after this experience I think that will be the next thing I learn. So far, the first AG is going well. Just finished the mash and am starting the boil. So we'll see from here. :tank:
 
I, too, threw a kolsch yeast (White Labs') into the freezer for a few while with the hops without thinking about it! A few posts I've read in the past (don't remember them at the moment) had people say they didn't have problems when yeast was frozen for a bit in the vial, but I guess it's better to be on the safe side.
 
This is from the Wyeast website under FAQ's

"17. What should you do if the yeast is frozen?

Thaw out in fridge. Activate and assess the time that it takes to swell. If there is no activation within 24 hrs, do not use. If there is activation, make a starter to revive culture. "
 
This is from the Wyeast website under FAQ's

"17. What should you do if the yeast is frozen?

Thaw out in fridge. Activate and assess the time that it takes to swell. If there is no activation within 24 hrs, do not use. If there is activation, make a starter to revive culture. "

Maybe I didn't give mine long enough to expand, but I was close to the LHBS and it's about 40 min from the house so I just got a new pack. After about 8 hours though, the "thawed" one hadn't expanded at all.
 
If I was a betting man I would say that a lot of the yeast in that packet is still viable. Like another poster recommended, make a starter and you'll know for sure.
 
Well it is way after the fact now, but there have been similar threads on here and the yeast came right back to life. I remember one, specifically, in which it was delivered and froze on his doorstep (thanks UPS). Maybe a week in the freezer is too much, but nature is pretty hardy.
 
The problem I had with making a starter is that I had nothing to make one one with. If I had to go to the LHBS to get DME....might as well have just bought new yeast, which i did! :D
 
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