Repitching Yeast After a Big Beer

[Oktober]

BNer's,

I was fortunate to get a growler-full of lager yeast from my local brewpub, which was pulled from a Dopplebock he had brewed ~2 weeks prior. At first I was a little concerned given that the yeast was going to be pretty stressed after coming out of the 9-10% beer. But I was not going to give up on the planned brew day, so I just overpitched the German Pils I was brewing with the yeast and have been keeping my fingers crossed.

With the remainder of the yeast, I figured I would dump it into a 2 L starter to multiply and possibly let it recover a bit. That got me thinking - because of the origin of this yeast (i.e. high ABV lager), if I run the yeast through a starter or two, will the yeast 'de-stress' so I can keep using it through a succession of lagers? Or has the "stress" somewhat irreversible and I should start growing up a fresh culture for my next lagers? How much off flavors can I expect to get out of stressed yeast like this?

Either way, the Pils is fermenting now and should be ready for lagering next week - hopefully I don't pick up any off flavors from the stressed yeast.

Please sound off with your thoughts.

Thanks!

-Okt

[brewinhard]

I make it a rule of thumb to NOT repitch yeast from beers that are 7% ABV or higher. From what I understand the higher alcohol levels not only stress the yeast but can cause mutations in the strain leading the beer to finish with a proper attenuation or even produce off-flavors as stressed yeast can (which you mentioned).

With that being said, many Belgian breweries only brew strong, high alcohol beers and they are therefore forced to repitch their yeast from one batch to another, at least for a few generations I would assume. Although they probably top crop their yeast taking a more viable, healthy portion from their fermentations.

If you are planning on doing a run of lagers, I would start fresh with a new culture and repitch from lower to higher ABV% beers in that order. Better to take the time and build your yeast up properly then continue repitching stressed yeast that might or might not produce off-flavors or fermentation issues in any random batch that you spent hard working hours/money brewing up. Good luck!
Hope your pilsner comes out clean!

[Oktober]

Thanks brewinhard.

I have two older vials of Pilsner Yeast in my fridge that I might start growing up for the next lager (Munich Dunkel) and get rid of the 'stressed' yeast that I have on a stirplate.

-Okt

[brewinhard]

I am still interested in finding out how your "stressed" yeast ( ) pilsner comes out. Please post back with results....

[mordantly]

I am still interested in finding out how your "stressed" yeast ( ) pilsner comes out. Please post back with results....

i have some 1056 that on it's third pitch went into a >32brix american barleywine that i was contemplating using on a foreign stout this weekend.. has your jury come back with a verdict yet??

[Bugeater]

In general I won't repitch a yeast after it has done a 1.060+ beer. When I'm doing a really big beer (1.075+) I always do a smaller beer first so I can use the yeast cake. I don't use the entire yeast cake. I save a portion of it to use on other beers rather than trying to salvage yeast from the big beer. By using parts of that saved portion, I often get 6-7 beers from the original one vial of yeast (grown with a starter for the first round) before I get tired of that yeast and want to use a different one.

Wayne

[Blunt]

I usually brew lagers with Fermentis 34/70 and usually around 2 or 3 batches off the same yeast cake/carboy in concession. As for ales I haven't had much luck coming off the same yeast cake/carboy but I have rinsed ale yeast for reuse with luck. As for pitching stressed yeast multiple times, it must be dependent on the yeast strains being able to withstand the stress of the high alcohol production.

[Oktober]

I am still interested in finding out how your "stressed" yeast ( ) pilsner comes out. Please post back with results....

I should be racking the pilsner into a corny this weekend, which is when I will get the first taste. After that, the beer will be lagering for another couple weeks before the final verdict comes in. I'll report back.

-Okt