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Author Topic: Lager Yeast Viability ?  (Read 904 times)

Offline quattlebaum

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Lager Yeast Viability ?
« on: May 18, 2015, 08:53:38 pm »
Do ya think that the viability of the yeast decreases significantly when the lager is set at higher temps for a a "diactyl rest" while left on the yeast cake? Say like 64 F for a week? Planning on brewing a Rye bock (1.060 OG)from a 2 week old lager yeast ( WLP833) that has been sitting at 64F for 7 days.

Offline troybinso

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Re: Lager Yeast Viability ?
« Reply #1 on: May 18, 2015, 09:08:42 pm »
Nope.

Lager yeast would just as soon be at 64 degrees than 50. It's just that the beer tastes better when you ferment at 50.

Offline ynotbrusum

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Re: Lager Yeast Viability ?
« Reply #2 on: May 19, 2015, 12:19:10 pm »
I use the Brulosopher step fermentation for lagers and have had much success.  Your situation may have a bit to do with how long the yeast fermented prior to the D-rest period.  If it wasn't too terribly long, then your yeast should be just fine for repitching.  If it was a month or more, then the D-rest was probably late and the warm temp may have taken a week to obtain the reducing effect on diacetyl, but the slurry should still be okay, unless you fermented for something like 8 weeks in the primary - then I would rack and do a starter with the slurry (a couple-three tablespoons or so), rather than relying on the slurry going directly to a 1060 beer. 

I also assume you are coming from a smaller ABV beer here.

Good luck with your rye bock! Sounds great.
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