Author Topic: Double Batch Fermentation  (Read 2206 times)

Offline arboyd72

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Double Batch Fermentation
« on: August 22, 2010, 11:09:35 PM »
I was thinking of upgrading my fermentation vessel for 10 gal batches.  What are your thoughts on making two 5 gallon batches of wort and fermenting them as a 10 gallon batch?  By this I mean to make the first 5gallon wort batch, move to fermenter and pitch enough yeast to ferment a 10 gallon batch.  Then make another 5 gallon wort batch and add that to the first batch already in the fermenter.

Offline tschmidlin

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Re: Double Batch Fermentation
« Reply #1 on: August 23, 2010, 01:00:03 AM »
There's no reason that won't work, a lot of breweries do it.

But I would question why you would want to.  I do the exact opposite, I brew 10 gallons and split it into two different carboys, it lets me use different yeasts in them to taste how they are different.  If I were spending your money, I would spend it to upgrade your brewing system to do 10 gallons so you didn't have to brew twice to fill the fermenter.  Then later maybe upgrade to fermenters for 10 gallons.

But like I said, there's no reason why what you're proposing won't work.
Tom Schmidlin

Offline jeffy

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Re: Double Batch Fermentation
« Reply #2 on: August 23, 2010, 04:14:52 AM »
There's also no need to pitch twice the amount of yeast.  By the time you're ready to add the second batch of wort, the initial pitch will have grown in volume enough to make quick work of it.
Jeff Gladish, Tampa (989.3, 175.1 Apparent Rennarian)
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Offline timmyr

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Re: Double Batch Fermentation
« Reply #3 on: August 23, 2010, 05:38:43 AM »
There's no reason that won't work, a lot of breweries do it.

But I would question why you would want to.  I do the exact opposite, I brew 10 gallons and split it into two different carboys, it lets me use different yeasts in them to taste how they are different.  If I were spending your money, I would spend it to upgrade your brewing system to do 10 gallons so you didn't have to brew twice to fill the fermenter.  Then later maybe upgrade to fermenters for 10 gallons.

But like I said, there's no reason why what you're proposing won't work.

I must say it sounds like a good idea, but is the opposite of what I do.  I prefer the 10 gallon batch split into two ferments to compare yeast or dry-hops or whatever.  I realized one day that 10-gal was the same amount of time and effort as 5-gallons (ok, maybe a little more effort).  I feel like I get more bang for my buck and time this way. 

In any case, please post your results,  I'd be interested int doing two small 2.5 gallon batches sometime and making 5-gallons of them maybe.
Cheers,

Timmy

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Offline majorvices

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Re: Double Batch Fermentation
« Reply #4 on: August 23, 2010, 07:11:20 AM »
+1 to just brewing 10 gallon batches. Makes no sense to double batch 5 when you can brew 10 for the same amount of time as 5. Heck, even the 10 gal kettles are not much more $$ than the 10 (or, more like 15 when you count head space)  Now, if you were going to double batch 10 into a 27 gallon blickmann conical that might be another story.
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Offline beerrat

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Re: Double Batch Fermentation
« Reply #5 on: August 24, 2010, 03:24:23 AM »
Just for some more clarity on options... again, if I make things to complicated, then remind me to RDWHAHB!

If one wanted a consistent beer for a tasting event, needed 10 gallons of it.  Any thoughts on the following limitations and how to address for having one consistent beer?

1) Capable of brewing 10 gallons, but limited by 5 gallon fermentations vessels.
When filling fermentation vessels, either make a tee to fill both carboys at once, or after every quarter, switch which carboy filling to blend wort to avoid one having all the break material.
After fermentation ends, blend beer  by racking 1/2 out of each carboy to the two 5 gallon kegs, rotating which keg gets the top of one, and bottom of the other carboy.

2) Limited to brewing 5 gallons, and 5 gallon fermentations vessels.
Split 1/2 of first brew into the 2 carboys,pitch least, aerate, and then brew next 5gal batch.  Split next wort into carboys, making sure the second one receives the top half of this wort, and the first carboy gets the bottom half (so one does not get all the break material.)

After fermentation ends, blend beer  by racking 1/2 out of each carboy to the two 5 gallon kegs, rotating which keg gets the top of one, and bottom of the other carboy.


Thoughts?
« Last Edit: August 24, 2010, 08:25:58 AM by beerrat »

Offline tschmidlin

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Re: Double Batch Fermentation
« Reply #6 on: August 24, 2010, 09:56:32 AM »
Just for some more clarity on options... again, if I make things to complicated, then remind me to RDWHAHB!
Yeah, RDWHAHB :)

I would just ferment them separately, whether it was 10 gallons split to 2 carboys or 2 x 5 gallons into 2 carboys.  Just fill them and go.  Then go get yourself a plastic garbage can or bucket that will hold 15 gallons - when the beer is done, rack both carboys to your "kegging bucket" and then rack to kegs.  It will blend well enough in the can to be uniform in the keg.

But maybe other people have other ideas.
Tom Schmidlin

Offline saintpierre

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Re: Double Batch Fermentation
« Reply #7 on: August 24, 2010, 10:11:56 AM »
I have used the plastic tees to seperate directly from the kettle and they work OKAY at best.  The flow is never uniform so you have to babysit and pinch the lines to get flow to equalize to each fermenter.
Having said that I still use this method and get basically identical OG readings from each fermenter.  However, I have been telling myself I need to tweak the system so I can walk away and have a homebrew.

Congrats on the upgrade!
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Offline wingnut

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Re: Double Batch Fermentation
« Reply #8 on: August 24, 2010, 10:17:22 AM »
The cheap and easy way is just to ferment two similar beers (mash on same day to reduce cleaning), and fill the two kegs half full with the two beers. (ie mix the fermented beers in the kegs).  Creating a bunch of tees and changing process is a recipe for headaches.  Keeping pretty much the same process will be much more enjoyable and have the same results!

Good luck, and isn't wonderful to have such a demand!!!   
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Offline timmyr

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Re: Double Batch Fermentation
« Reply #9 on: August 31, 2010, 07:07:13 PM »
I have used the plastic tees to seperate directly from the kettle and they work OKAY at best.  The flow is never uniform so you have to babysit and pinch the lines to get flow to equalize to each fermenter.
Having said that I still use this method and get basically identical OG readings from each fermenter.  However, I have been telling myself I need to tweak the system so I can walk away and have a homebrew.

Congrats on the upgrade!

+1  I drain and fill one carboy then the other.  I do watch the drain off my kettle in case I think I might run short on one or need to fill a little low at first on one, but I typically plan 12 gallon+ batches so I usually get 5.5 gallons into the carboy, unless I've had one of many "complications" as I drain off my kettle.
Cheers,

Timmy

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