Author Topic: Advice on lager and reusing the yeast cake  (Read 873 times)

Offline wort-h.o.g.

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Advice on lager and reusing the yeast cake
« on: April 28, 2013, 07:29:07 AM »
I'm interested in brewing 4 consecutive Czech pilsner lagers, reusing the wlp 802 yeast. I have never done this before, and need some advice on how to go about this. If the first round is on the yeast cake for about 3 weeks before I rack it to the corny for lagering, do I rinse the cake and just transfer the clean yeast into my clean carboy, and then add my new wort to the entire harvested yeast? How do I know if there's enough healthy yeast cells for the next lager- proper pitch rates?

Thanks in advance.

Offline klickitat jim

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Re: Advice on lager and reusing the yeast cake
« Reply #1 on: April 28, 2013, 07:49:35 AM »
I did it for the first time last weekend. I brewed two lagers last month. On keg day I rinsed the yeast cake with a quart of sterile h2o and poured it into sterile jars. Cold crashed in the fridge overnight. Decanted the next day. Had about 3/4 cup of slurry. I pitched that in a three liter starter to wake it up a couple days before brew day.

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Offline davidgzach

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Re: Advice on lager and reusing the yeast cake
« Reply #2 on: April 28, 2013, 09:51:10 AM »
I did it for the first time last weekend. I brewed two lagers last month. On keg day I rinsed the yeast cake with a quart of sterile h2o and poured it into sterile jars. Cold crashed in the fridge overnight. Decanted the next day. Had about 3/4 cup of slurry. I pitched that in a three liter starter to wake it up a couple days before brew day.

"Friends don't let friends drink bad beer"

That's how you do it!  Or you can transfer, scoop out about half and re-pitch right on top.

Dave
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Offline wort-h.o.g.

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Re: Advice on lager and reusing the yeast cake
« Reply #3 on: April 29, 2013, 08:45:25 AM »
I did it for the first time last weekend. I brewed two lagers last month. On keg day I rinsed the yeast cake with a quart of sterile h2o and poured it into sterile jars. Cold crashed in the fridge overnight. Decanted the next day. Had about 3/4 cup of slurry. I pitched that in a three liter starter to wake it up a couple days before brew day.

"Friends don't let friends drink bad beer"

That's how you do it!  Or you can transfer, scoop out about half and re-pitch right on top.

Dave

seems like many just collect the slurry without rinsing/washing it and separating out the trub, and add the new wort. not sure if there's a best practice to follow, or if its just one of those things that there isn't an agreed upon or "right" method.  seems easily debatable either way - pro's and con's for both?

Offline Thirsty_Monk

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Re: Advice on lager and reusing the yeast cake
« Reply #4 on: May 05, 2013, 05:06:41 PM »
Cleanliness (not introducing unwanted microorganism) is more important then rinsing the yeast.

Roughly you need about 1/2 of yeast cake for your lager for the same volume and similar OG.
Check with yeast calculators for more accurate info.

Good luck.   
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Offline reverseapachemaster

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Re: Advice on lager and reusing the yeast cake
« Reply #5 on: May 06, 2013, 06:32:21 AM »
If you are brewing right away on the cake then there's usually no real benefit to rinsing first unless you added something to the first beer in the fermentor that might carry through (spices/coffee/chocolate/etc.). If you are brewing four beers consecutively on the same yeast it might be worthwhile to rinse the yeast after the second or third batch just to reduce the amount of trub you have in the fermentor, especially if you are using a fermentor with minimal head space.
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Offline weithman5

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Re: Advice on lager and reusing the yeast cake
« Reply #6 on: May 06, 2013, 06:43:28 AM »
i will do lagers about 3 in a row.  i just go right on top of the previous cake.  i try to always be going up in gravity as i go (scuccessive starter theory 8)
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