can i carbonate beer with fermentation gas.

[fluketamer]

i know i have seen simialr topics but its hardto search for this specifically.

i am pretty sure i have seen lots of times where people purge kegs with gas from a pressure feremnter by daisy chaining them and putting the spunding valve at the end.

can you do the same hting with full kegs and carbonate them that way or is there a problem with this. if i jump the gas post from my pressure fermenter to the liquid post on a keg , and then spund the other end will it carb the keg. i know the keg will get stirred up from gas bubbling through the beer from the dip tube but it will always settle later in the kegerator is there any issue with carbonating beer with fermentation gas?

 

[hotbeer]

Aren't there undesirable flavor/aroma notes carried off with the fermentation CO2? Perhaps they precipitate out during the time you'll have it stored.

 

[day_trippr]

I routinely purge a pair of kegs with every 10 gallon batch, but it would take at least "chart pressure" coming out of a fermentation vessel to carbonate beer held at a favorable temperature (ie: the colder the better). Figure at least 11~12 psi. And one would need to make sure any oxygen existing in the fermentation vessel had been scrubbed before sending the gas to the keg(s).

So...it could be done, I suppose, with the right gear (pressure-capable fermentor) and setup (kegs well chilled)...

Cheers!

 

[mac_1103]

Aren't there undesirable flavor/aroma notes carried off with the fermentation CO2? Perhaps they precipitate out during the time you'll have it stored.

Why wouldn't they still be carried off through a spunding valve, whether it's on the FV or a keg connected to the FV?

one would need to make sure any oxygen existing in the fermentation vessel had been scrubbed before sending the gas to the keg(s)

A 40 gravity point ferment of 20 liters of wort produces over 400 liters of CO2, and it only takes 50 liters of CO2 to carbonate 20 liters of beer to 2.5 volumes, right? So there should be more than enough CO2 available to purge the FV headspace and then carbonate (a) refrigerated keg(s). As long as you start out with a blow-off and don't get too greedy.

it could be done, I suppose, with the right gear (pressure-capable fermentor) and setup (kegs well chilled)...

Yeah, if you want to do this at ambient temperature then you'll have to spund at something like 25-30 PSI. Having no experience with pressure fermenting I'll leave it to others to say whether that's a bad idea.

 

[fluketamer]

so i hooked up a cold keg two days ago and it seemed to be working so i daisy chained another one yesterday and it still seemed to work. then this morning i smelled a little sulfur coming out of the spund on the second keg. i figured i didnt like that sulfur bubbling up through my beers so i got scared and took them off.

my beer usually stops blowing sulfur after a few days and im am looking to reattach after.

however i dont fully understand pressure fermenting yet and im not sure if the spund will slow down the sulfer blow off and make it take forever to vent the smell. still having fun so far tho.

 

[hotbeer]

Why wouldn't they still be carried off through a spunding valve, whether it's on the FV or a keg connected to the FV?

I don't know enough to say they would or wouldn't. But depending on how many other kegs or other pressure vessels the OP is daisy chaining to and the volumes in them for gas, the "dirty" CO2 might not get pushed out by the cleaner CO2 produced later in the fermentation.

But I am very much just guessing and suggesting considerations. Pressure fermenting is something that I'm slowly acquiring some information about that is just interest at the moment. And this is sort of a twist.

Though the spunding pressure it'd take to carbonate the beer to acceptable levels for drinking seems like it'd be much higher than typically recommended.

And I'm not sure why the beer wouldn't be carbonated in it's own FV. Pressure transfer of the beer to a keg from the FV should be easy. And even bottling isn't that big a deal, though needing some extra equipement to do it right. But that can be DIY'ed.

If carbonating in the same FV is desired then the volume of headspace for gas would probably get rid of the earlier CO2 that might have those off aromas/tastes. But again, even that is something I don't know about. When is the CO2 carrying those off. Or does it even carry those off?

 

[fluketamer]

anyone else use a "shank tank"