Author Topic: how to re use yeast  (Read 548 times)

Offline jimrod

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how to re use yeast
« on: November 21, 2011, 12:36:35 AM »
How do you re use yeast that has a lot of O.T.Y......other than yeast....I have a lager still in the primary but it has all kinds of hop debris on the bottom of the 15 gal fermentor. ......How do you separate the yeast from the trash or do you just put the next beer right on top of the last beer old hop debris and all.
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Offline davidgzach

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Re: how to re use yeast
« Reply #1 on: November 21, 2011, 06:17:25 AM »
How do you re use yeast that has a lot of O.T.Y......other than yeast....I have a lager still in the primary but it has all kinds of hop debris on the bottom of the 15 gal fermentor. ......How do you separate the yeast from the trash or do you just put the next beer right on top of the last beer old hop debris and all.

There's a lot of info about yeast washing on the internet.  You need a few mason jars or the equivalent (I use 1L Powerade bottles) sterilized.  After racking leave a layer of beer on top.  Pour in 1-2 cups of boiled and cooled water, swirl it up to a nice slurry and pour in to your sterilized jars.  I usually take an alcohol swab and clean around the top of the fermenter where it will be poured. Place the jars in the fridge and wait 20-30 minutes.  You will see the slurry separate to trub on the bottom, yeast in the middle and the water on top.  Pour the water and yeast in to another jar and you have your first wash. 
Dave Zach

Offline Joe Sr.

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Re: how to re use yeast
« Reply #2 on: November 21, 2011, 09:23:25 AM »
or do you just put the next beer right on top of the last beer old hop debris and all.

Sometimes, yes.  You can do this and the typical approach is to go from lighter/weaker to darker/stronger beers (e.g. brew a light lager, use the yeast cake for a dopplebock).

Or, you can pour the yeast cake into a sanitized container and wash the yeast as mentioned above.

Or, you can pour it out and use only a portion of the total cake for your next batch which minimizes concerns about over-pitching.

There are several ways to go about it.  Find out which works best for you and go with that.
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Offline davidgzach

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Re: how to re use yeast
« Reply #3 on: November 21, 2011, 09:31:17 AM »
or do you just put the next beer right on top of the last beer old hop debris and all.

Sometimes, yes.  You can do this and the typical approach is to go from lighter/weaker to darker/stronger beers (e.g. brew a light lager, use the yeast cake for a dopplebock).

Or, you can pour the yeast cake into a sanitized container and wash the yeast as mentioned above.

Or, you can pour it out and use only a portion of the total cake for your next batch which minimizes concerns about over-pitching.

There are several ways to go about it.  Find out which works best for you and go with that.

+1.  If you are really worried about the amount of trub, then the wash is the best way.  I have found that it really doesn't make a difference.  I typically fill 2 1L containers half-way and just pitch one entire slurry in my next brew.  If you want to pitch on top of the cake, that's fine, but like Joe said, make sure it's to a much higher gravity beer.
Dave Zach