Building A Cpbf Without O2 Purge.

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How would that work? How can the beer get flat in a sealed bottle, where does the Co2 go to?

I tend to believe that once Co2 is in the bottle it stays in there, regardless of the filling method.

It gets knocked out of solution due to the turbulent flow created when moving it from keg to bottle - regardless of filling method. Commercial CPBFs work becuase they fill several bottles per second so the amount of time between filling and capping is very small.

Any brewer thinking they are not introducing O2 during the filling process and reducing carbonation is fooling themselves. Or recreating fundamental laws of physics. I suspect the former.
 
It gets knocked out of solution due to the turbulent flow created when moving it from keg to bottle - regardless of filling method. Commercial CPBFs work becuase they fill several bottles per second so the amount of time between filling and capping is very small.

Any brewer thinking they are not introducing O2 during the filling process and reducing carbonation is fooling themselves. Or recreating fundamental laws of physics. I suspect the former.

Read edited post above (in fact even the unedited post you quoted). How would Co2 escape from a bottle once capped? I can't see how.
 
Maybe I should be even more clear: I get that Co2 gets knocked out when filling, but Nick is saying that a bottle filled from the tap stays carbonated for the first 48 hours, then becomes flat. I don't think that works unless you don't know how to cap.
 
So you can pour a beer with a dip tube at atmospheric pressure and it'll stay carbonated?

BS. Why do CPBFs exist if this works?
You tell me. Is your beer flat the instant it comes out of the bottle/tap? As Florian said (in addition to what I said before), once the system is closed again, the only carbonation loss will be to the equalisation with the head space. I've opened up growlers after 4 weeks that are still adequately carbonated, even though they were filled from a tap.

Advantages of a CPBF include reduction of oxygen pickup during transfer, and you don't need a long beer line between the keg and the bottle.

I thought this too. Instead of wasting bottle gas would it be possible to use one of these to flush the bottle then use the method posted by the OP?
Bottled gas is going to be a hell of a lot cheaper than the cost of those canisters.

It gets knocked out of solution due to the turbulent flow created when moving it from keg to bottle - regardless of filling method. Commercial CPBFs work becuase they fill several bottles per second so the amount of time between filling and capping is very small.

Any brewer thinking they are not introducing O2 during the filling process and reducing carbonation is fooling themselves. Or recreating fundamental laws of physics. I suspect the former.
I don't think anyone is saying that you don't lose carbonation (I'm certainly not, hence my comment about starting with a higher carbonation and limiting headspace). And purging/filling under pressure is about reducing oxygen, not eliminating it.


Back to the OP; try it - I reckon it'll be fine for at least a couple of months if you store it cold. If you're concerned about losing carbonation, start at a higher level to compensate for the loss.

Cheers,
tallie
 
Maybe I should be even more clear: I get that Co2 gets knocked out when filling, but Nick is saying that a bottle filled from the tap stays carbonated for the first 48 hours, then becomes flat. I don't think that works unless you don't know how to cap.
The only way is if it's escaping into the headspace.

If the beer isn't foaming as you are pouring it I don't think you're losing much CO2 (or your beer was flat to begin with).

I exclusively used the slow pour method for over a year but got sick of the taste changing slightly (which I put down to oxidation) so I got a CPBF. The beers really weren't much less carbonated.
 
I, too, have many beers that are over 6 months old using the BMBG. Perfect carbonation, just like it came from the faucet.

If you cap on foam and, like BM said, condition the beer right, I see no reason why these shouldn't last a long time.

Why do you think the carbonation level will drop? Same caps, same crimp, CO2 foam...?

For anyone wondering about long-term storage with this method, I just cracked open a bottle of last year's Oktoberfest lager with a date of 10/08 on the cap. I bottled it right from the chilled keg and sat it on the shelf at room temp. It was re-chilled a few weeks ago. It was exactly as I remember it a year ago - carbonation was great and no off flavors.

For what it's worth, I found this page earlier in the year and have been using this technique all year long to pull bottles from keg for sharing and for competition. I had a quite successful competition year with positive comments about the quality of carbonation virtually every time on my scoresheets.

Well it seems to work well for these guys with no loss of carbonation. Unless of course theyre all lying.

Im going to give it a try, would work well for when you want to bottle some beers from your keg to take to a party or a mates house for the night.
 
I never said it would lose CO2 once capped but that it would be lower than in the keg.

You would also get an ingress of O2 during the filling process and between stopping the filling and capping leading to oxidation.
 
There's two types of bottle filling:

1. It lasts 48 hours and is then flat.

2. Counter pressure bottle filling, done at a bee's dick less than keg pressure.

I was always under the impression that the transfer should be done at higher than keg pressure when using a CPBF, in other words raise the serving pressure of the keg higher than the beer is carbonated to, purge and pressurize bottle at the higher pressure and fill while venting, stops any foaming.

Well it seems to work well for these guys with no loss of carbonation. Unless of course theyre all lying.

Is it possible their beers are still fermenting slightly in the bottle and that is helping with the pressure? Any time I have used the tube or dribble method there has been a marked difference between the bottle carbonation after 48 hours and the kegged beer carbonation, the bottle beer being very flat.i
And don't forget the co2 that will come out of the beer to equalize the pressure in the head space of the bottle, a bt like coke gets flatter the more you drink.
 
Read edited post above (in fact even the unedited post you quoted). How would Co2 escape from a bottle once capped? I can't see how.

p.s. it won't escape but it will re-equilibrate (thus descreasing the carbonation level in the beer due to the headspace) ;)
 
Depends how long you shoot Co2 in there. I'm pretty wasteful to be honest and usually flush for a good 10 seconds on 50 to 100 kpa and also move the hose while doing so. There shouldn't be much oxygen in there after that, especially if you consider that there's only about 21% oxygen in air.

It's still total overkill considering those beers get drunk on the same night anyway. Comps are a different story, works well for those.

I don't know about Dalton's law, but you only need enough c02 to accumulate at the bottom of the bottle and then to ride up on the beer and fill the headspace.

The Blichmann beer gun manual says to spray another squirt of c02 in as you remove the wand, then cap on foam
 
If they are filling the bottle from the bottom to push the air out the top, then tipping the bottle slightly to create some foam and capping on top of foam how can there be any air still in the bottle?

Wouldnt the foam push out the last bit of air in the headspace? That seems to be the key to this.
 
So you can pour a beer with a dip tube at atmospheric pressure and it'll stay carbonated?

BS. Why do CPBFs exist if this works?

It works with the beer gun. You can fill a bottle with absolutely no foam/head quite easily.

Why do cpbfs exist? Because the beer gun hadn't been invented yet I guesss
 
p.s. it won't escape but it will re-equilibrate (thus descreasing the carbonation level in the beer due to the headspace) ;)

That makes sense, I hadn't thought of that when posting.

In the past I have subconsciously avoided that problem by overfilling the bottles right up to the brim.
This has also been noted on my comp scoresheets, without point deduction, so i will keep doing it as I haven't lost any points for low carb either.
 
If they are filling the bottle from the bottom to push the air out the top, then tipping the bottle slightly to create some foam and capping on top of foam how can there be any air still in the bottle?

Wouldnt the foam push out the last bit of air in the headspace? That seems to be the key to this.

Yerp, commercial bottling lines sometimes shoot a jet of water into the filled bottle to cause a foam explosion just before capping, even if they've counter pressure filled.

So, two parts, one is preserving c02, the other is avoiding 02

I wonder what sort of difference it makes not doing the c02 pre-purge, because that's the basic difference with the beer gun. That and a 10ft 3mm hose ;) (or whatever it is)
 
I use the " poor mans" bottle filler method all the time. Works very well!

Piece of tubing in the end of a picnic tap, to the bottom of the bottle with a rubber stopper at the top - to all the nay sayers yes it does work. Have you tried it?

I give the bottle a good flush CO2 (20secs) prior to filling and make sure everything is cold.

I fill at round 70kpa, after the initial burst into the bottle the pressure equalize with the keg and no more beer will actual enter the bottle until i push on the rubber stopper with my finger. By the the time i get to the top there is no foam (escaping CO2) at all.

You have to slowly remove the stopper to allow the pressure to be released, i tiny squirt of beer at the top ( capping on foam) and very quickly cap.

I have kept these in the fridge for up to a month with no to very little loss in quality. Beyond that i would say that the O2 that is in there will start to do more damage.

This method is surprisingly easy and quick, i can knock out 4 - 6 PET tallies in under 10mins.

I originally looked into CPBF and BBG but this method leaves me wondering why i would want to spend that kind of money them?
 
I was always under the impression that the transfer should be done at higher than keg pressure when using a CPBF, in other words raise the serving pressure of the keg higher than the beer is carbonated to, purge and pressurize bottle at the higher pressure and fill while venting, stops any foaming.



Is it possible their beers are still fermenting slightly in the bottle and that is helping with the pressure? Any time I have used the tube or dribble method there has been a marked difference between the bottle carbonation after 48 hours and the kegged beer carbonation, the bottle beer being very flat.i
And don't forget the co2 that will come out of the beer to equalize the pressure in the head space of the bottle, a bt like coke gets flatter the more you drink.

Yes. That's also what I do. My comment though, was that the pressure in the bottle must be at a slightly lower pressure than the keg (hence "counter pressure") done by bleeding the purge valve to allow beer transfer.

I also don't know how these people are doing it. If I pour using a dip tube and virtually eliminate foaming ... in 48 hours any remaining Co2 has come out of solution and entered the headspace leaving the beer lackluster and what most people would describe as flat.

However, if I just pour quickly into a bottle and cap it - it's fine for about 6 hours. CO2 doesn't leap out of solution at atmospheric temp.

I think your "fermenting a little bit" in the bottle might also explain some people's long term results - especially considering they added oxygen during transfer...
 
Read edited post above (in fact even the unedited post you quoted). How would Co2 escape from a bottle once capped? I can't see how.

Try this.

Get a cold commercial bottle of beer. Open it.

Take it to your capper and cap it.

Wait a week. Still fizzy?

Report back. ;)
 
There shouldn't be much oxygen in there after that, especially if you consider that there's only about 21% oxygen in air.

But why wouldn't there be any air/oxygen left, isn't the point of partial pressures that the CO2 will be added to the existing air that is in the bottle instead of displacing it? (genuine interest here - not trying to say your wrong as i'm possibly way off the mark)
 
But why wouldn't there be any air/oxygen left, isn't the point of partial pressures that the CO2 will be added to the existing air that is in the bottle instead of displacing it? (genuine interest here - not trying to say your wrong as i'm possibly way off the mark)

It's there, it's just sitting on a blanket of CO2 because O2 is lighter.

Nick, the fermenation would've halted on a commercially available beer as no company would want their yeasts reused/pilfered by another brewing company. The beers a lot of us tend to make still have the yeast active, hence the slow buildup over months/years of that protective CO2 blanket. :icon_cheers:
 
Try this.

Get a cold commercial bottle of beer. Open it.

Take it to your capper and cap it.

Wait a week. Still fizzy?

Report back. ;)

Well, I think we have established that the secret lies in the head space.

When I fill my bottles up to the brim with beer no Co2 can escape into the head space.


Try this.

Get a cold commercial bottle of beer. Open it. Fill it to the brim with beer from another freshly opened bottle.

Take it to your capper and cap it.

Wait a week. Still fairly fizzy?

Report back. ;)
 
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