Very foamy pours

[reckoner]

Hi all,

Hoping for some help - I've spent hours Google and troubleshooting but still having trouble.

Basically I'm having foam issues. I'm using 6.5L corny kegs, cold crashing to 4 degrees C, then pressurizing to 30psi for 24-36 hours before purging the pressure and lowering to 8-10psi for serving.

However I'm getting mostly foam, probably 80% - finding it almost impossible to get even a 1/4 glass of beer. I've checked my beer line length and everything else I can think of - about a 2m line, 4mm ID (sorry imperial folk), and a beer connector with flow reg.

The beer doesn't feel over carbonated, temperature seems about right... I'm out of ideas.

Any advice or a push in the right direction would be really appreciated. Thanks in advnace.

 

[SFC Rudy]

Do the math.

1. Piece of advice, ignore everyone’s “rules of thumb”. Unless they have the exact same system that you have what they do will not work right for you

2. Pick a carbonation method:

https://byo.com/article/3-ways-to-carbonate-your-keg-techniques/

https://byo.com/article/carbonating-options-kegging/

3. Use a keg line length calculator. https://www.kegerators.com/beer-line-calculator/

4. Use this calculator to fine tune your system. https://content.kegworks.com/blog/determine-right-pressure-for-your-draft-beer-system/

Do the math and avoid problems.

 

[tracer bullet]

Usual culprit is line length and diameter. I can't say if yours is exactly right but agree to check. At least you've got that considered (though perhaps not correct, I can't say).

I'd check all the connections, sometimes there's an o-ring at issue, it can let air in as the beer rushes by.

Might simply be over-carbonating it to start with, that psi and time could simply be too much.

That' where I'd go.

 

[scrap iron]

Tell us more about the ''beer connector with flow rg'' and is the line length 2 meters. [about 6 feet]
I don't know of the setup you have but co2 comes out of solution at warmer temps.

 

[mac_1103]

I'd check all the connections, sometimes there's an o-ring at issue, it can let air in as the beer rushes by.

A dip tube o-ring leak could also let CO2 get into the beer as it's being poured, which would lead to extremely foamy pours even if everything else is perfectly balanced. Same thing can happen with a floating dip tube that isn't floating right.

 

[Velnerj]

I'd bet the remaining beer in my keg that your beer line is too short. I had similar issue (and similar practice). I doubled the beer line from 2m to 4m and it worked much better.

 

[mac_1103]

I'd bet the remaining beer in my keg...

OK, so how much beer is left in your keg?

 

[Broken Crow]

I'm using 6.5L corny kegs, cold crashing to 4 degrees C, then pressurizing to 30psi for 24-36 hours before purging the pressure and lowering to 8-10psi for serving.

IMHO: Likely overcarbed; I do approx 19L @ 28psi for 24-36 hours.....your 6.5L kegs are about a third of the volume of the full-sized 5G cornies that most people cite similar numbers for. If it's one of those popularish chinese baby-kegs it's a bit wider so has a greater surface area of CO2 exposure and just a rough guess (my brain is broken) I suspect it would have reached your desired CO2 volume by only 12 hours or so. Just leave it sit at serving pressure, drawing the occasional sample until it settles.

 

[Deadalus]

I too think that perhaps you are leaving the pressure on too long with the temperature also starting low.

I go the over pressure route and use 30 psi initially. I will then shake the keg a few times and wait for the gas to stop flowing. Then I turn off the gas. I come back later that day or even the next and do this again. Depends on when I remember to. Then a a day or two later I will switch to the equilibrium pressure and let it sit. About a week in I will start to pour and see if it's ready. If after a couple days when you set it to equilibrium pressure you find that turning the gas on does not result in gas entering the keg, you are overcarbonated so bleed off some gas and cut the CO2. Then try again the next day. I'm not usually overcarbonated though because I don't leave it set at 30 psi. I just let it absorb what's in the headspace and come back. Usually I'm working with 5 gallon kegs or 2.5-3 gallons although I have done it with smaller kegs too. If you have a spunding valve, you could also set to your equilibrium pressure and put it on the overcarbonated keg to release CO2.

 

[mac_1103]

I'm using 6.5L corny kegs

Sorry, I misread this as 6.5G. I think @Broken Crow is probably on to something. The 30 PSI for 24 hours rule of thumb is based on a five gallon batch in a five gallon keg.

 

[Deadalus]

If it equalizes at that temp it would have around 4.2 vol.

 

[Velnerj]

OK, so how much beer is left in your keg?

Not quite sure, but just now, there's one pint less.

 

[SacSudz]

Assuming you've already verified your line length is correct I can offer another thing to look at. And that is to completely disassemble your keg connections and faucet and clean them. When I was a rook I never did that and had foamy beer. I then opened everything up and was surprised to see how much gunk was in my keg fitting. Once cleaned out no more problems.

 

[camonick]

You don’t mention what kind of faucet you’re using to dispense with. Assuming it’s not a stout faucet with a restrictor plate installed (which would automatically be your problem), but rather a “regular” forward or rear sealing bar faucet or picnic tap, you are operating at either full open or full closed? You can’t successfully “throttle” the flow with them without having a foamy mess.
… just something to consider.

 

[reckoner]

Thanks everyone. This has given me a lot to think about.

I am using a cheap picnic tap that's either fully open or fully closed, so I potentially need to find myself a better one.

As for the beer line, I'll order a longer length and try increasing it.

And in case I've overcarbonated the beer, I have another keg that's almost done fermenting so I'll try 28psi over 6-12 hours instead of 25 given it's a small keg. Or maybe I'll stick with 10-15psi for a few days instead of the higher pressure... I'll do some research.

I did do a check of all the keg seals a few weeks ago so I don't know if that's the culprit, but I will re-check.

Thanks again, I'll keep troubleshooting.

 

[tracer bullet]

And in case I've overcarbonated the beer, I have another keg that's almost done fermenting so I'll try 28psi over 6-12 hours instead of 25 given it's a small keg.

If it's setup right maybe just have it connected to the picnic tap and unhook it when it seems ready? I suppose you'll have to shut off the valve to it and pull the PRV so not as easy as it sounds.

You mentioned the picnic tap, if it is indeed full open that's good. If you try to throttle it a bit it actually makes it much worse.

I force carb my kegs by setting the regulator to 12 psi and rolling them on the floor until the gas quits going in, about 8 minutes for a 3 gallon eg and maybe 15 minutes for a 5 gallon keg. This is when warm, so that might be helping. Then it goes in the frig at the 12psi serving pressure I use for about a day or two to be cold and it's always perfect afterwards. I think the rolling and massive surface area both allow the CO2 to dissolve into it really quickly. You can do it with one hand and read the news on your phone with the other, or have something on TV while you wait.

 

[reckoner]

If it's setup right maybe just have it connected to the picnic tap and unhook it when it seems ready? I suppose you'll have to shut off the valve to it and pull the PRV so not as easy as it sounds.

You mentioned the picnic tap, if it is indeed full open that's good. If you try to throttle it a bit it actually makes it much worse.

I force carb my kegs by setting the regulator to 12 psi and rolling them on the floor until the gas quits going in, about 8 minutes for a 3 gallon eg and maybe 15 minutes for a 5 gallon keg. This is when warm, so that might be helping. Then it goes in the frig at the 12psi serving pressure I use for about a day or two to be cold and it's always perfect afterwards. I think the rolling and massive surface area both allow the CO2 to dissolve into it really quickly. You can do it with one hand and read the news on your phone with the other, or have something on TV while you wait.

I'm experimenting with fermenting and serving out of the same keg at the moment, so can't move the keg around too much or the trub stirs up at the bottom. So I think I might have to just be patient and go with a lower co2 pressure over a longer period of time, rather than trying to carbonate too quickly

 

[tracer bullet]

I'm experimenting with fermenting and serving out of the same keg at the moment

Haha, yeah, definitely don't do the roll thing!

 

[refect]

Thanks everyone. This has given me a lot to think about.

I am using a cheap picnic tap that's either fully open or fully closed, so I potentially need to find myself a better one.

As for the beer line, I'll order a longer length and try increasing it.

And in case I've overcarbonated the beer, I have another keg that's almost done fermenting so I'll try 28psi over 6-12 hours instead of 25 given it's a small keg. Or maybe I'll stick with 10-15psi for a few days instead of the higher pressure... I'll do some research.

I did do a check of all the keg seals a few weeks ago so I don't know if that's the culprit, but I will re-check.

Thanks again, I'll keep troubleshooting.

I've had foaming issue from time to time. I usually fill my 5 gallon corny kegs to about 4.5 - 4.75 gallons. I used to do the same method as you and burst carb at 30 psi for about 24 - 36 hours (Sometimes even 48 hours). I'd then purge and drop it to about 10 - 12 psi (depending on beer style and temperature). My beers would start out great, but eventually foam way too much as time went on.

I now only burst carb for about 12 - 16 hours at 30 psi just to get a jump on carbonation, but then I purge the headspace and use the force carbobation chart to get it the rest of the way with the set and forget method. Usually after a week to a week and a half it is fully carbed with this method and not over carbonated.

I use about 6 feet of 4mm evabarrier line and don't have too many issues with the method above, except on the first pour. I usually just pour out the first 3 ounces since it is usually flat and oxidized from sitting in the lines for a week or so, but after doing that the first pour is much more manageable.

I have also had an issue with the dip tube o ring going bad and allowing co2 to enter the line, which caused insane foaming on every pour. You might want to check there as well as others have mentioned.

One thing I've noticed as well is my beers tend to kick up much more foam as the kegs get closer to empty. I think this has something to do with having a larger headspace and the fact that heat rises so it is likely colder at the bottom and causes higher co2 volume as the beer gets down to the colder bottom. However, even when this happens, my pours are pretty manageable when using the method above. When I was leaving it at 30 psi for much longer, it would result in much much more foaming as it got closer to the bottom of the keg, which is why I now only burst carb for about 12 - 16 hours at 30 psi, and then switch to set and forget method to get it the rest of the way.