Foamy keg

jeffpn

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The fourth keg that I've done is giving me a foamy pour. It results in about 1/3 beer and 2/3 foam in the glass. I've been looking around for advice on how to deal with it, but it nothing seems to make it any better. My first 3 kegs are all great. I may have left this keg at 30 psi for 3 days instead of 2 like I did the other ones.

I have a new theory that I want to ask if anyone has seen. Suppose that there's a pinhole leak at the top of the beverage dip tube. This could be either a physical hole through the tube, a crack in the flange at the top of the tube, a faulty o-ring around that dip tube, a gouge in the seat where the tube sits, or something similar. I can visualize where this could cause gas in the headspace to mix with beer as it's being dispensed. If this theory were the case, I believe it wouldn't matter if the beer had no carbonation. It would still come out foamy due to the "injection" of CO2. Has anyone of heard of foamy beer being caused by such a thing? I'm wondering if it's worth depressurizing the keg and taking the liquid side apart to inspect and test it. I'm also considering racking this beer into another keg to see if it behaves any better. Then I could fill the keg in question with water to see if it mixes with CO2 as it's being dispensed. I don't want to disturb my batch any more than necessary.
 
I have had this happen. My problem always resulted in over gassing the beer. I normally have 30 psig on the beer for two days and then put it back to serving pressure. When over gassed I take the gas off the keg and release the gas on the keg by pulling the relief valve. Doing this a few times during the day will normally take care of the foaming.

Dan
 
Yes. I've done that. It hasn't even begun to solve my problem. I'm curious if anyone has ever experienced the theory that I presented.
 
the main issue with beer foam is cold meeting warm somewhere, usually your faucet is warmer than the beer, also just a tip, all beer will foam more as the keg is about to empty, also a fresh washed glass will foam the first beer, then not even half as much pouring the second and less the third, its the coating on the glass and the glass being warmer than the beer, I use 3/16" hose longer than needed but stuff the extra down the sides of the kegs keep in the beer in the line cold, you can also chill your glasses
 
These kegs are full. All of the lines are entirely refrigerated. My faucets are cold to the touch. Inside line diameter is 1/4". Lines are 10' long. Cold mugs, soap residue. Thread after thread that I found on the subject addresses all of these points.

My question is has anyone ever seen a situation where a keg had a defect that allowed CO2 slip into the beer dip tube in the headspace, causing bubbles in the line even if the keg was full of water? The theory seems plausible to me. I'm only wondering if anyone has actually seen it.
 
this is why we purge or kegs often, also going to 3/16 id line will cut down most foam
 
My other 3 taps I have online now pour perfectly. They are all set up the same way. Something is different on the one keg. I'm only wondering if it is in the realm of possibility that a keg could have a defect that allows CO2 to mix with the beverage in the headspace, just before the beer leaves the keg to go through the lines. It seems plausible to me that that could happen. Has anyone ever known that to happen?
 
open the lid while you pour a beer, if you see bubbles in that line, its probably a bad connection somewhere. it happens, just unplug and reposition the line
 
I've done that. There are bubbles in the line. That's why I'm asking if anyone has ever seen a faulty seal on the liquid dip tube that allows gas from the headspace to enter the outgoing liquid stream inside of the keg. No gas or liquid is leaking outside the keg. If there is a leak, it's entirely inside the keg. I can visualize this scenario. Like I said, it seems plausible to me. I'm only asking if anyone has experienced it.
 
you can unhook all those parts and inspect the tube popit or the o-rings, just takes a wrench
 
I took it entirely apart to clean and sanitize before I filled the keg. I did not think to carefully inspect the surfaces for gouges, pinholes, etc. Before I go to the trouble of disassembling a full keg, I was wondering if anyone has ever experienced the issue that I described.
 
Have you taken the serving line off the foaming keg and put it onto another keg that isn't foaming?
 
I did that last night. Poured fine. I hooked up the keg in question to another tap which was pouring fine with another keg. It was foamy. Whatever is going on is the batch itself, or the plumbing in the keg.
 
There is a possibility of a pin hole leak in the dip tube.

More likely: The poppet may be defective, if it's not opening fully for some reason you will have foaming issues, or I guess potentially something else causing blockage
 
I agree with the poppet being suspect. Either that or the beer is just over carbonated.
 
The Brew Mentor said:
I agree with the poppet being suspect. Either that or the beer is just over carbonated.
I have had a poppet do that. Was difficult to trace out. If you swap the fitting on the keg with one you know works that would tell you. Wouldn't have to pull the dip tube.
 
Keg # 5 poured great right out of the gate. I'll sheepishly admit that I may have overcarbed # 4. Probably better off to undercarb, really. It'll get to the same carb level as the others. It has to. It's physics.

Beer Mentor, it just dawned on me that 440 is an Ohio area code. Hadn't really stopped to look at your number before. Got me wondering if you happen to be in Mentor. I see you are. I have family up there. I've also been to the Lake County Captains stadium several times. I think I've posted that I'm near Dayton.
 
Beer Mentor, it just dawned on me that 440 is an Ohio area code. Hadn't really stopped to look at your number before. Got me wondering if you happen to be in Mentor. I see you are. I have family up there. I've also been to the Lake County Captains stadium several times. I think I've posted that I'm near Dayton.[/quote]

Yes, we're in Mentor.
The name of the shop is a play on words.
Our goal is to "Mentor" our customers with beer and wine making. We also roast coffee and have made cheese.
Next time you're in town, stop in. I may have something you need. :lol:
You may also want to check out an event we have planned with the city.
http://cityofmentor.com/play/upcomingev ... or-on-tap/
35 Ohio Craft Breweries in one place at one time! Food, Bands, etc.
Cheers
Brian
 
It seems that a couple of my kegs don't have gas bubbles in the lines, and a couple kegs do. Interestingly, the 3 lines that develop bubbles have slightly longer shanks than the 2 lines that don't develop bubbles to speak of. The bubbles seem to form fairly quickly, like while I'd drink a glass and pour another one. I'm thinking that the shank length would have little to do with this. I did set the temp a tad colder, and increased the pressure by 1-2 psi. Any thoughts on which way to go when gas bubbles only occur on some lines and not others? All the kegs are on the same manifold. I have 10' of 1/4" ID line on every tap, coiled and laying on top of the kegs. No fan, 36°F cabinet setting. I'm considering testing 3/8" ID line.
 
once carbed turn your pressure down to about 5 psi and use 3/16" id hose, you see a huge difference.

the bigger the hose and higher the pressure, more foam will appear
 

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