Using Fermentation CO2 to Carbonate Beer?

Bulin's Milker Bucket Brews

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Assuming one had vessels capable of being pressurized AND you purged with CO2 first, if you connected a keg to your fermentor with a regulator to keep the pressure right...Anybody here tried it?
 
Assuming one had vessels capable of being pressurized AND you purged with CO2 first, if you connected a keg to your fermentor with a regulator to keep the pressure right...Anybody here tried it?

You're somewhat on the right track. More or less the answer is yes. You need a tank capable of handling pressure and what happens is that as your beer ferments under pressure, it carbonates itself with the co2 it creates during the process. You need the correct gear. The basics being a fermenter to handle and a spunding valve. You can even capture the o2 discharged during fermentation in another vessel that can be used for transfers etc. I'm sure there's others here using the process, but I know myself and @Trialben have been posting recently about this topic.
Here's at least one thread for reference. https://www.brewersfriend.com/forum/threads/fermzilla-conical-fermenter-v2.11950/page-3#post-89871


what are you doing with home brew today

What are you drinking right now?

what are you doing with home brew today


It's fun! You can go from grain to glass in less than a week. @Trialben just went 5 days and drinking. I think mine was 6 or 7 days?
 
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You can carb the beer that's fermenting with no trouble. Just close off the fermenter vessel - assuming that's it's close-off-able and rated for the proper pressure.
If you're talking about carbing up a separate keg of finished beer using the CO2 produced from a current batch, not so much.
Breweries large and small are starting to use CO2 re-capture systems but that's a different animal altogether. That requires a lot of plumbing and high-pressure pumps
 
Yep thanks to all the cool new relatively low coast affordable options pretty much anyone can pressure ferment/purge recieving vassal.
Even a corny keg will do.
Good luck any questions fire away.
 
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I do it all the time, instead of an airlock i hook up a hose from my fermenter to a keg, then from the keg to a bottle full of sanitiser water to purge the keg with pure co2 from the fermentation process, then i push the beer to the keg approximately 8 points above final gravity, and let it finish fermenting in the keg with a 15psi spunding valve, then in the kegerator i push with co2 or nitrogen.

Im a low oxygen brewer, my system is very complex, i have adapted my system to eliminate as much oxygen ingress as possible from start to finish.

I do not push my brewing views and opinions on anyone, i let my beer speak for itself. If you are interested in learning more about low o2 brewing feel free to pm me.

Here is my house helles
 
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I think my primaries would be up to it. They are 10 gallon heavy gauge stainless milker unit pails.

For those of you that have been doing it already, how has fermenting under pressure affected you attenuation and how do you control your level of carbonation?

I use mainly lager yeast any particular strains that work better under pressure?
 
You want a certain volume of co2, for me as i brew many lagers, i am spunding between 6 and 10 points above final gravity. I perform a fast ferment test to determine my final gravity for each said beer. This generally allows me 10 to 12 volumes of co2 in the beer. I have no issue with fermentation under pressure i spund in my korny kegs.
 
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This generally allows me 10 to 12 volumes of co2 in the beer.
What??? 10 to 12 volumes??! Average carb level is 2.5 volumes.
 
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Last batch was first batch fermented under pressure. Yeast was S-23 fermentis fermented at 17c and psi was 18 attenuation was 78% grist has over 400g of crystal malt so I'm happy with that FG was 1.010.
One thing I've noticed is krausen is heaps smaller under preassure this batch was 1cm max. I also finished that fermentation at 19c to help attenuation. The yeast are supposed to produce less esters whilst fermenting under preassure and at 17c and less than a week on this beer it tastes pretty clean to me.
 
@ja i will double check my numbers, i believe you are correct i think i meant to say 2 to 2.5 volumes.
 
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@ja i will double check my numbers, i believe you are correct i think i meant to say 2 to 2.5 volumes.
That makes sense...I close off at about 4 points short of gravity - usually about the time I raise for diacetyl rest with lagers. My pressure relief valve goes at somewhere between 18 and 20 PSI so at 68 degrees or so I'm carbed to at least 2 volumes. When I drop temp for yeast harvesting and/or lagering I'll top up the pressure so that I'm pushing around 2.5 volumes before transfering to kegs, figuring I may lose a little CO2 out of solution in the transfer. Once it's in the keg, I'll top up as needed for a week or so and settle at a nice serving pressure and temp.
 

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