Author Topic: 3 week old yeast  (Read 847 times)

Offline gmac

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3 week old yeast
« on: March 25, 2012, 08:18:51 PM »
I have the yeast collected from a 5 gal batch of Saison (Wyeast French Saison) that's been in the fridge for about 3 weeks. It is unwashed and the full amount. Can I pitch it as is into another 5 gal batch or should I wash it and put it in a starter?

Offline The Professor

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Re: 3 week old yeast
« Reply #1 on: March 25, 2012, 09:49:55 PM »
I have no experience with saison yeast, but I have harvested ale yeast and used it as much as 2 months later with no issues, other that a somewhat slower start.  If in doubt, feed it up beforehand...it will probably work fine.
AL
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Homebrewer since July 1971

Offline Mark G

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Re: 3 week old yeast
« Reply #2 on: March 26, 2012, 05:24:12 AM »
At 3 weeks, I'd just use it as-is. Maybe pitch a slightly larger amount of slurry to compensate.
Mark Gres

Offline ccfoo242

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Re: 3 week old yeast
« Reply #3 on: March 26, 2012, 06:44:38 AM »
There's a harvest date parameter for repitching on mr. malty's pitch calculater: http://www.mrmalty.com/calc/calc.html

When I put in a date that is 3 weeks ago I get 61% viability...definitely make a starter with it unless you have enough already to compensate for the dead yeast.

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Offline brewmichigan

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Re: 3 week old yeast
« Reply #4 on: March 26, 2012, 07:00:54 AM »
How much slurry? I would tend to agree with Mark G. If you have enough, pitch a slightly larger amount. Wyeast says that a slurry in the fridge for 2 weeks is straight pitchable. Anything after that they recommend either a starter or pitching more to compensate. You're good.
Mike --- Flint, Michigan

Offline gmac

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Re: 3 week old yeast
« Reply #5 on: March 26, 2012, 07:18:20 AM »
Thanks.  There's at least a liter of slurry so I will just pitch it all.  Gravity target is 1.052 so it's not a high gravity beer anyway.