Nitro "beer gas" question

[Ron Reyes (Papa Piggy)]

Im using a beer gas mixture of 25% co2 and 75% Nitro for my stouts and porters. My first couple beers/kegs were great. First up was a dry stout then a porter. My third and present beer is the same porter recipe. I pre carbonate the kegs with straight CO2 for a week or so then i switch it over to my Nitro tank and serve till its done. The third and present batch started out ok for the first few pints. But now its as if all the CO2 is gone. there is plenty of Nitro to push the bear out but its pretty flat with no head at all. So im wondering if somehow the gas has separated? Or something else? the beer tastes great but the appearance is all wrong.

 

[Nosybear]

Well, for one, while it is statistically possible for gasses to separate, the probability is so low that you can assume it will never happen. I'd look elsewhere for the lack of head retention. Most likely is soapy glassware.

 

[Ron Reyes (Papa Piggy)]

Well, for one, while it is statistically possible for gasses to separate, the probability is so low that you can assume it will never happen. I'd look elsewhere for the lack of head retention. Most likely is soapy glassware.

hmmmm ok i didn't think so. I doubt it's the glassware cause my other beers on tap come out fine. and even if it was glassware wouldn't i still get the cascading effect? it just would not last right? Im not getting ANY cascade at all. its coming out fine but flat. also im serving at 30-35 psi

 

[Steve SPF]

Really interested in this. I'm intending to start testing a 30/70 mix because my favourite brewer advised that it would make the beer more stable in situations where the ambient temperature is a factor.

Can I ask what's the logic behind carbing with CO2 and then switching to a mix for dispense?

On the question of flat beer, as @Nosybear said it's often a residue somewhere that the beer doesn't like. Our techies always tell us to start there when we bitch at them over flat beer.

If you've eliminated glassware as a cause then what else can it be? Could the keg have leaked the CO2 away so you're dispensing un-carbed beer? Could the keg itself have been missed out in the cleaning round prior to filling? Are the beer lines clean?

I guess there are a few places to look.

 

[Nosybear]

Don't just look for soap, look for fats and oils as well.

 

[Steve SPF]

Don't just look for soap, look for fats and oils as well.

Amen to that, beer hates grease.

 

[Ron Reyes (Papa Piggy)]

the first few pints were fine. same glasware used on my other beers with no problem. no leaks. I had a leak at one point that drained my tank. after that i always check everything with a star san spray for leaks

 

[GFHomebrew]

So your serving at 30psi and your not getting any cascading up the glass or any head on the pour? It would be comming out into the glass pretty quick at 30psi I would believe eh?

It's a real cueveball it's hard to believe no head at that pressure.
Kegs nice and cold?
I like Steve's Ideah on a good line clean I always find a bump in head retention after a line clean.

 

[Ron Reyes (Papa Piggy)]

So your serving at 30psi and your not getting any cascading up the glass or any head on the pour? It would be comming out into the glass pretty quick at 30psi I would believe eh?

It's a real cueveball it's hard to believe no head at that pressure.
Kegs nice and cold?
I like Steve's Idea on a good line clean I always find a bump in head retention after a line clean.

i tried 35 psi and 40 psi. and now im getting a tiny head and signs of cascading. only has 3 batches of beer have gone through the system and in between each keg I flush with warm PBW then warm clean water then star san. i leave the starsan in the line until the keg is purged of oxygen then i drive a little fresh beer through the lines to get rid of the starsan. after pressurization i flush the lines and then always get great pours.

 

[Mase]

You might have a stuck poppet with hop debris or something. 35-40psi would not be pourable, the beer would be gushing out at that psi.

 

[Steve SPF]

40psi? Wow. Is the regulator working properly? Surely 40psi would be blasting away like a fire extinguisher?

All of ours work at 10-12psi for both mixed and straight CO2. Anything over that and the beer is over carbed and we get nothing but foam. It's weird that 40psi can dispense flat beer. Weird.

 

[Ron Reyes (Papa Piggy)]

You might have a stuck poppet with hop debris or something. 35-40psi would not be pourable, the beer would be gushing out at that psi.

wouldn't a stuck popet result in either too much carbonation or none at all?

 

[Ron Reyes (Papa Piggy)]

40psi? Wow. Is the regulator working properly? Surely 40psi would be blasting away like a fire extinguisher?

All of ours work at 10-12psi for both mixed and straight CO2. Anything over that and the beer is over carbed and we get nothing but foam. It's weird that 40psi can dispense flat beer. Weird.

30-35 is widely excepted as normal for this scenario. I just boosted it to 40 to see if that would help. And it did so clearly as far as i can tell the beer itself is not carbonated properly and the Nitro is just pushing it out. Since the same system resulted in a couple great kegs and this keg when i first started pouring the problem is most likely not systemic but some anomaly.

 

[GFHomebrew]

You'd expect a quick lively pour at 40psi.

 

[Ron Reyes (Papa Piggy)]

You'd expect a quick lively pour at 40psi.

the restrictor disc prevents....... hm wait that may be it. im gonna clean the whole tap and see what i get.

 

[Nosybear]

40psi? Wow. Is the regulator working properly? Surely 40psi would be blasting away like a fire extinguisher?

All of ours work at 10-12psi for both mixed and straight CO2. Anything over that and the beer is over carbed and we get nothing but foam. It's weird that 40psi can dispense flat beer. Weird.

Second that. At that pressure, it wouldn't be cascading, it would be exploding, regardless of the gas mixture.

 

[Ron Reyes (Papa Piggy)]

Second that. At that pressure, it wouldn't be cascading, it would be exploding, regardless of the gas mixture.

it seems weird how people are shocked by 40 PSI. While it is at the high range and certainly higher than i have ever had my nitro mix set at. it IS within recommended range by several sources i have found on line. here is what Kegwors says on their web page.

"Most beers are dispensed somewhere in the range of 10 to 15 PSI. If you are pouring a nitro beer, that range increases to 30 to 40 PSI."

 

[GFHomebrew]

it seems weird how people are shocked by 40 PSI. While it is at the high range and certainly higher than i have ever had my nitro mix set at. it IS within recommended range by several sources i have found on line. here is what Kegwors says on their web page.

"Most beers are dispensed somewhere in the range of 10 to 15 PSI. If you are pouring a nitro beer, that range increases to 30 to 40 PSI."

Did you find a fix there ron by cleaning out the tap?
Maybe you gotta just drink this one as is get it out the way and move onto the next one.

 

[Ron Reyes (Papa Piggy)]

Did you find a fix there ron by cleaning out the tap?
Maybe you gotta just drink this one as is get it out the way and move onto the next one.

Ill have time to clean it tomorrow and let you know

 

[Ron Reyes (Papa Piggy)]

Did you find a fix there ron by cleaning out the tap?
Maybe you gotta just drink this one as is get it out the way and move onto the next one.

BINGO!!!! i took the faucet apart and while it did not look dirty at all i guess a couple of the tiny holes must have been clogged. I just poured a perfect pint with awesome cascade and super creamy head. yummmmm