Racking / reuse question

[OmegaRed]

I have a Blonde Ale going right now. (2) 5 gallon batches in separate 6 gallon carboys. That being said, I am planning on making a twenty gallon batch here after this gets kegged. I do BIAB / No chill, so I can time them out.

My question is, can I rack off the existing fermented wort and keg, then pour my newly brewed wort directly onto the existing slurry, aerate and continue? Or should I chill, decant, and wash the yeast? Will the existing slurry give off flavors etc. ?

Thanks...just trying to reuse whats already there if possible.

 

[MrFeltimo]

Just rack chilled wort onto/into carboy, great healthy yeast waiting for more food.
I do it all the time, last one, IPA onto APA took of like a rocket, within 3hours i had to install a blowoff tube.
No need to worry about off flavours, unless they are drastically different beer.

 

[flars]

A 5 gallon starter would seem about right for 20 gallons of new wort.

 

[shtoive87]

I would rack onto 1/4 of the slurry if you can but there's no issue with using what's in there already

 

[MrFeltimo]

I would rack onto 1/4 of the slurry if you can but there's no issue with using what's in there already

i would say NO.

 

[kombat]

I would rack onto 1/4 of the slurry if you can

Note that the OP is going from two 5 gallon batches to a 20 gallon batch. 1/4 of the slurry from one carboy would be appropriate for another 5 gallon batch, but given the 300% step-up in volume, the repitching the entire slurry from one of the 6 gallon carboys is appropriate.

 

[MagicMatt]

Note that the OP is going from two 5 gallon batches to a 20 gallon batch. 1/4 of the slurry from one carboy would be appropriate for another 5 gallon batch, but given the 300% step-up in volume, the repitching the entire slurry from one of the 6 gallon carboys is appropriate.

Note that the OP wants to "pour my newly brewed wort directly onto the existing slurry" in the 6 gallon carboy. Regardless of batch size, this means ~5-6 gallons of wort onto the yeast cake from a 6 gallon carboy - IOW, a bit too much.

Also, going from 10 gallons to 20 gallons is only a 100% increase in volume.

 

[flars]

Note that the OP wants to "pour my newly brewed wort directly onto the existing slurry" in the 6 gallon carboy. Regardless of batch size, this means ~5-6 gallons of wort onto the yeast cake from a 6 gallon carboy - IOW, a bit too much.

Also, going from 10 gallons to 20 gallons is only a 100% increase in volume.

You might be right. OP may be planning to fill each of the carboys with new wort, holding back the remaining 10 gallons until the next two carboys ferment out, and then repeating.

That would be massive over pitching, especially with the last 10 gallons.

Need clarification from OP.

 

[OmegaRed]

I'm glad I asked. I have the flexibility to do it multiple ways. I have enough carboy and ferm chamber capacity to do all 20 gallons at once. Or I could do 10, then 10 two weeks later.


Just to clarify what you guys have said, if I do all 20 gallons at once, just take one of the current 5 gallon carboys, divide the slurry into 1/4 of the volume, and repitch 1/4 into each of the (4) carboys with fresh wort.

OR...

If I repitch into 2 different sets of 10 gallons, then 10 gallons; I need to remove even more.

 

[kombat]

Note that the OP wants to "pour my newly brewed wort directly onto the existing slurry" in the 6 gallon carboy. Regardless of batch size, this means ~5-6 gallons of wort onto the yeast cake from a 6 gallon carboy - IOW, a bit too much.

Agreed, that part was a bit ambiguous. I'm not sure how he plans to dump 20 gallons of wort onto the slurry in a 5 gallon carboy. I guess I figured he'd be collecting the slurry from one carboy and distributing it amongst however many fermenters he's using for the 20 gallon batch.

Also, going from 10 gallons to 20 gallons is only a 100% increase in volume.

I was assuming he was only planning on using the slurry from one (5 gallon) carboy to inoculate his new 20 gallon batch. 5 gallons to 20 is an increase of 300%.

 

[MagicMatt]

Just to clarify what you guys have said, if I do all 20 gallons at once, just take one of the current 5 gallon carboys, divide the slurry into 1/4 of the volume, and repitch 1/4 into each of the (4) carboys with fresh wort.

This sounds like the most feasible solution, unless you have a reason for not wanting to ferment all 20 gallons at one time.

 

[OmegaRed]

This sounds like the most feasible solution, unless you have a reason for not wanting to ferment all 20 gallons at one time.

Nope that sounds perfect. I'd rather do it all at once so it's only one cleaning session. I'm trying to get ramped up to my full 45 gallon capacity for a big party coming in June. Then I also want to have stuff ready in the carboys so I'm not out of beer for a long time.