Storing Used Lager Yeast

[BryanEBIAB]

I’ve been trying my hand at the “continuous use” method of refilling my uncleaned fermenter immediately after emptying it (loving it!). My problem is my fermentation temperature control still needs work so as summer warms up, I want insurance in case my yeast get stressed and I didn’t want to reuse them. I decided to save a quart of slurry in a mason jar and stick it in the back of the fridge (sorry Wife) as per random advice on the internet. The jar was thankfully not too tight as this was yeast after all. After a week or two, I noticed it was fermenting! I realized my problem: this was lager yeast (SafLager S-23) and they were laughing at my feeble attempt to make it dormant in a mere refrigerator. I was just lagering a quart of beer in a jar!

So anyway, is freezing lager yeast the only way to save used slurry for extended periods? Would that even work? Does anyone have a preferred method to do this? I’m not sure I want to freeze liquid in glass so what to use instead? Sanitized Tupperware?

It’s not a big deal to just start fresh; it’s more a matter of pride to use the same yeast as many times as I can.

Thanks, Folks!

 

[JohnSand]

I put mine in mason jars in the fridge, with the lid slightly loose at first.

 

[GoeHaarden]

So anyway, is freezing lager yeast the only way to save used slurry for extended periods? Would that even work? Does anyone have a preferred method to do this? I’m not sure I want to freeze liquid in glass so what to use instead? Sanitized Tupperware?

You can freeze yeast in a 1:1 solution of yeast slurry and 50% glycerin. Ultimately making the glycerin 25%. I only do this is 30mL tubes and use stepped up starters to get back going, but I don't know about doing large quantities though. I've also never frozen the used cake, always pulled from a fresh starter.

I freeze a few vials of each new strain, but for quick turn around I just put some yeast in a pint mason jar in the fridge like suggested...

 

[Sammy86]

The yeast will go dormant after fermentation so it‘s really not a big deal. I leave mine in the fridge and don’t have any problems creating starters with them and repitching.

 

[odie]

just refrigerate the yeast. it will be fine. lid on loosely so it can gas off.