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Author Topic: New Wort onto a Yeast Slurry  (Read 698 times)

Offline HopDen

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New Wort onto a Yeast Slurry
« on: August 14, 2023, 02:47:25 pm »
Currently fermenting a Czech Lager with 34/70

I want to add a new wort on top of said yeast. Ideally right after kegging, assuming I keg on brew day but not sure I will. With that said, I have a couple questions

1) Can I leave the yeast under cover of CO2 in the fermenter for 7 days at 55* (basement temp) until brew day?
2) Would the yeast be viable after those 7 days?

Offline denny

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Re: New Wort onto a Yeast Slurry
« Reply #1 on: August 14, 2023, 03:34:29 pm »
Currently fermenting a Czech Lager with 34/70

I want to add a new wort on top of said yeast. Ideally right after kegging, assuming I keg on brew day but not sure I will. With that said, I have a couple questions

1) Can I leave the yeast under cover of CO2 in the fermenter for 7 days at 55* (basement temp) until brew day?
2) Would the yeast be viable after those 7 days?

You need to keep beer on top of it. If you do that, should be no problem. Another consideration is, do you really want to use all of it?  I have found I get better results by using only 1/3-1/2 of a slurry.
Life begins at 60.....1.060, that is!

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Offline HopDen

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Re: New Wort onto a Yeast Slurry
« Reply #2 on: August 14, 2023, 03:56:35 pm »
Currently fermenting a Czech Lager with 34/70

I want to add a new wort on top of said yeast. Ideally right after kegging, assuming I keg on brew day but not sure I will. With that said, I have a couple questions

1) Can I leave the yeast under cover of CO2 in the fermenter for 7 days at 55* (basement temp) until brew day?
2) Would the yeast be viable after those 7 days?

You need to keep beer on top of it. If you do that, should be no problem. Another consideration is, do you really want to use all of it?  I have found I get better results by using only 1/3-1/2 of a slurry.

Good point on having beer on top. Obviously when I collect slurry for re-pitching there is beer that rises to cover the yeast. I have a SS conical and IIRC there is about a gallon of beer that remains behind so I should be ok. I could drain some out of the bottom valve but it would be a guess as to how much I'm actually leaving behind.

Offline Kevin

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Re: New Wort onto a Yeast Slurry
« Reply #3 on: August 15, 2023, 11:11:49 am »
I've done this in the past. I plan my brew day to coincide with kegging day of the batch currently in the fermenter. As Denny says you don't need to pitch on top of an entire yeast cake. I have done that however when the new beer going into the fermenter is high gravity beast in the neighborhood of 1.100 OG and it has worked very well.
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Offline denny

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Re: New Wort onto a Yeast Slurry
« Reply #4 on: August 15, 2023, 12:16:46 pm »
I've done this in the past. I plan my brew day to coincide with kegging day of the batch currently in the fermenter. As Denny says you don't need to pitch on top of an entire yeast cake. I have done that however when the new beer going into the fermenter is high gravity beast in the neighborhood of 1.100 OG and it has worked very well.

Yes, it ferments well, but seems to develop more flavor with some yeast growth.
Life begins at 60.....1.060, that is!

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Offline Kevin

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Re: New Wort onto a Yeast Slurry
« Reply #5 on: August 16, 2023, 08:08:36 am »
I've done this in the past. I plan my brew day to coincide with kegging day of the batch currently in the fermenter. As Denny says you don't need to pitch on top of an entire yeast cake. I have done that however when the new beer going into the fermenter is high gravity beast in the neighborhood of 1.100 OG and it has worked very well.

Yes, it ferments well, but seems to develop more flavor with some yeast growth.

I dunno... My RIS made that way scored 43.
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Offline denny

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Re: New Wort onto a Yeast Slurry
« Reply #6 on: August 16, 2023, 08:51:34 am »
I've done this in the past. I plan my brew day to coincide with kegging day of the batch currently in the fermenter. As Denny says you don't need to pitch on top of an entire yeast cake. I have done that however when the new beer going into the fermenter is high gravity beast in the neighborhood of 1.100 OG and it has worked very well.

Yes, it ferments well, but seems to develop more flavor with some yeast growth.

I dunno... My RIS made that way scored 43.

Maybe it could have been a 50! But, yeah, full slurry is probably less of an issue for big beers. For average or slightly above normal, my experience is that a bit less works better.
Life begins at 60.....1.060, that is!

www.dennybrew.com

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"The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts." - Bertrand Russell

Offline ynotbrusum

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Re: New Wort onto a Yeast Slurry
« Reply #7 on: August 16, 2023, 11:00:10 am »
In the past I would start lagers with a 2-3 gallon size, step up with the whole slurry to 5 gallons, then continue to 10 gallons with the whole slurry; thereafter harvest when next brewing (back when I was brewing weekly and could use it directly from harvest into chilled aerated wort in the second fermenter) with a "couple/three" scoops of a stainless ladle that held about 3 ozs.  That seemed to do the trick for quick, healthy ferments and I took one such yeast out to 25 batches...yeast growth is a good thing.

Congrats on your 43.  I once had a 43 for a lager score and it didn't place at the comp.  Some stiff competitions (every place was won by a nationally known homebrewer, so I didn't mind the result).
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Offline Kevin

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Re: New Wort onto a Yeast Slurry
« Reply #8 on: August 17, 2023, 08:49:00 am »

Congrats on your 43.  I once had a 43 for a lager score and it didn't place at the comp.  Some stiff competitions (every place was won by a nationally known homebrewer, so I didn't mind the result).

Thank you. Same here... it didn't place but I was happy. The judges notes were all positive.
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