Best way to transport a keg- Pressurized headspace or no?

[micraftbeer]

In these COVID times, we'll have neighborhood gatherings in the common grassy area in our subdivision on weekends from time to time. I load up a couple cornys on a wagon and roll out there- all of maybe 150-200 ft.

I end up with huge amounts of foam in my picnic tap beer lines, and oftentimes can go 3-4 hours out there without ever having to hook up CO2, because the beer is just so foamy.

It had me wondering if there was a transportation trick with either depressurizing the headspace before a shaky transport, or is it best to leave it at serving pressure?

 

[TheMadKing]

In these COVID times, we'll have neighborhood gatherings in the common grassy area in our subdivision on weekends from time to time. I load up a couple cornys on a wagon and roll out there- all of maybe 150-200 ft.

I end up with huge amounts of foam in my picnic tap beer lines, and oftentimes can go 3-4 hours out there without ever having to hook up CO2, because the beer is just so foamy.

It had me wondering if there was a transportation trick with either depressurizing the headspace before a shaky transport, or is it best to leave it at serving pressure?

Definitely leave it with some pressure. Kegs need pressure to seal, so if you depressurize it, you could lose your seal and let air in.

You are getting foam because of a combination of moving it and the temperature increasing and possibly some issues with your line length

You can help with the foam by letting your keg sit still for a bit after moving it, keeping your keg and lines colder using ice, making sure you have 7-10' of 3/16" ID beverage tubing, and serve at 4-5 PSI instead of ~10 like you probably do in your keezer.

If you do this regularly you should also see about getting everyone to pitch in and buy a jockey box.

 

[Vale71]

Depressurizing will actually cause the beer to foam even more. I'm afraid the only real solution is to move the kegs well in advance and let them rest for a few hours before tapping them.

 

[NeoBrew]

I assume you are talking about Corny kegs?

If you are getting foam from a full keg it is caused by temp and pressure not being shaken. Corny kegs pull from the bottom as do most kegs. Even sitting a couple minutes would let liquid beer settle to the bottom of the keg where the dip tube is. If the keg is not full, I could imagine that might make things worse, but not to the point where sitting for 3-4 hours.

As has been mentioned, work on the temp of your system first. Are you keeping the keg on ice? Are you chilling the whole keg or just the bottom? If it's in a garbage can of ice or something, throw a blanket over the top? Keep as much of the line as you can on the ice as well.

Are you using a picnic tap to serve? The length of line to the tap may also be letting too much CO2 out of solution. Try a longer line for that?

 

[micraftbeer]

Here's some more information on my set-up, and some thoughts on what might be going on based on a thought I had, plus the comments here.

Full details of configuration

1. 5 gallon Corny kegs with fixed dip tube.
2. Keezer temperature is around 32-35F (before I pull keg out).
3. Keezer pressure is 12 psi.
4. Mobile set-up uses Cool Brewing insulated keg bag (Amazon link here) + their keg cooler ice sheet.
5. Picnic tab/cobra tap with 6 feet of 3/16" ID line (sitting outside the bag).

Thinking about this some more, here's where I'm thinking the temperature is getting to me. At a high level, I've had worse luck with foaming in summertime gatherings than in the fall (serving line temperature difference). I could probably improve things by keeping my beer line inside the keg cooler bag and just have a short length at the end sticking out. Could probably get even better by getting some foam pipe insulation to put over that length of tubing that sits outside.

The other thing I'm thinking about can be traced with a keg carbonation chart. As good as the keg bag + ice wrap is, it can't keep up with keezer temperature. So my dissolved Vols of CO2 work to liberate themselves into the headspace, so within the keg, it's acting like an over-carbed keg. I haven't measured the temp inside my keg bag, but I can give this a try as I have a wireless bluetooth Inkbird thermometer, and I'm now very curious. But here's my walk on a carbonation chart (which now has me re-thinking my keezer pressure setting...)

• At 33F & 12 psi, that's 2.83 Vols of CO2.
• But at 38F (guess of temp inside the bag) & 2.83 vols of CO2, it needs 15 psi to keep that Vols of CO2 in solution.
• So my keg with headspace pressure at 12 psi can't keep the CO2 in solution and it starts to free itself.
• So in theory, my mobile keezer set-up would want 15 psi of CO2 to stay in balance.

So I would maybe want even longer beer line length, combined with this higher CO2. Or maybe if I could prepare in advance, I could attach a spunding on my keg in the keezer to drop its pressure and let it equalize to a lower Vols of CO2 prior to "field day", and then I could dispense at a more normal pressure level.

 

[Golddiggie]

What beer are you carbonating THAT high? Seriously, you're in the 'highly carbonated' range there. IMO, that's why you have so much foam coming out of the keg. If you're serving ales (not Belgians) then you should look to reduce the CO2 levels to something more reasonable.

For my ales, I typically target about 2.4-2.5 CO2 volumes (12psi at 40-41F). I typically get great pours at these levels. Even when I've moved a keg, via truck about 20 minutes, and set up in a bucket of ice, I didn't have glasses of foam (or even half glasses). That was with a picnic tap (5' of line IIRC). I also didn't need to wait hours before pouring the beer (first glass was less than 20 minutes from when I arrived, with it in the bucket of ice).

 

[micraftbeer]

Yeah, I need to double check things on my keezer. Way back when I started my keezer, I was going for 2.4 Vols and I figured out the pressure. But then I improved my keezer design and have much better/even cooling, but never adjusted the target pressure in my mind. I use an ITW GovReg for the pressure, so it's pretty stable (but an extra hassle to check the pressure).

I'm happy with the pours out of the keezer, but maybe I can back off the pressure there and shorten my lines inside to keep the 8-10 second pint pour.

 

[micraftbeer]

I just checked my pressure on one of my kegs using my Spundit spunding valve, which has a pretty good pressure gauge. It's reading 13.5 psi, so I'm definitely over-carbed. So completely aside from my mobile keg question, I may have stumbled up on why I still get the occasional larger than wanted head of foam on my keezer. Even with 10 seconds to pour a full pint of beer (dialed in with liquid line length to slow it to this point), and a keezer layout that has the shanks at 35F (measured with wireless bluetooth thermometer with lid closed).

The other stuff mentioned above will still come into play, but I will get my keezer pressure dialed back to around 8 psi at my cold temps.

 

[Golddiggie]

Yeah, I need to double check things on my keezer. Way back when I started my keezer, I was going for 2.4 Vols and I figured out the pressure. But then I improved my keezer design and have much better/even cooling, but never adjusted the target pressure in my mind. I use an ITW GovReg for the pressure, so it's pretty stable (but an extra hassle to check the pressure).

I'm happy with the pours out of the keezer, but maybe I can back off the pressure there and shorten my lines inside to keep the 8-10 second pint pour.

What's your main regulator off the CO2 bottle? I was using a Taprite secondary regulator while using a carbonating corny keg lid (until I shifted to carbonating in fermenter) which was accurate. I was ONLY using that for the carbonating process. Nothing else. I do have a dual body regulator coming off my CO2 bottle (20#) feeding a pair of manifolds (one per body) so I can set different pressure levels as I wish. That's also a Taprite regulator. I can also adjust the CO2 pressure easily since all my gas bottles are outside the keezer. More room for kegs that way, plus EASY to adjust pressures or check fill levels. I don't like to open up the keezer unless it's necessary. IMO, checking the pressure levels feeding the kegs is NOT one of those. I have three gas bulkheads going through the keezer collar. Two for CO2 and one for nitro/CO2 mix.

 

[micraftbeer]

I have a dual gauge taprite regulator on a 20lb CO2 tank that's outside my keezer. I pass that through my keezer collar and then have the GovReg connected before going into my 8 tap gas manifold, so all 8 get the same pressure feed. I used to have a regulator at each keg but that manifold just took up too much space inside my keezer with all its knobs and gauges. Plus I never really set anything to a different pressure.

If you're not familiar with the GovReg, here's the link to my review, which also had some pictures of how it saves space in my keezer:

https://www.homebrewfinds.com/2020/...r-by-itw-pressure-regulator-technologies.html

 

[JJinMD]

I repurposed my 10 gallon igloo mashtun cooler as a keg cooler, cornies fit perfectly in there, so much that I bought a few extra for just this purpose. As stated earlier, the corny is drawing off the bottom, so the top few inches out of the ice are no big deal. Then, I use about 10 ft of evabarrier beer line, wrap most of it around the corny submerged in ice bath and leave 2-3 feet hanging out for serving with a picnic tap. With this setup, I have loaded up the minivan, and used a handtruck to transport the kegs several miles to parties. Never had a foaming problem that couldn't be solved with a quick adjustment to the regulator.

 

[micraftbeer]

I had success yesterday in serving beer in the field without massive foam. After the above discussion where I realized my keezer pressure setting was overcarbing my beer, I adjusted the keezer pressure down to get me back to the 2.4 Vols I had been targeting. (I also purged the kegs and let them readjust to this new lower carbonation level.) I kept about half the length of serving line inside the keg cooler bag as well, but my guess is that getting the keg carbonation back to a reasonable level was the key here to success.