Foam, carbonation and kegging

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snails07

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Picture this:

An ice cold lager (XXXX, Carlton Draught, VB etc) poured at a pub in a schooner glass with an inch of head and bubbles that never stop rising off the bottom. That is how I want my beers to pour.

The beer that comes out of my taps have a lot more foam than needed and isn't very 'effervescent'.

I've been drinking beer for over 20 years and brewing for 6 or 7 years, but I still don't fully understand how carbonation, foam, head retention, serving pressure and carbonation pressure all play together when kegging.

It's mainly pale ales and IPA's on tap.

When I set up my keezer I used the carbonation charts and line calculator to work out if I aim for about 2.4vols at 4c I will need about 10 PSI and about 10 or 12 feet of 5mm line (can't remember exact length).
The taps are intertap flow controls on a tower without a fan. It is not only the first pour, but all pours that are like this.

Would simply increasing the line length help? Or do I need to reduce pressure?
How do I get the bubbles without the massive, dense foam head.

All lines and taps are cleaned and sanitized regularly.
 
How do you initially carbonate? Force carb for a couple of days or serving pressure for a week or so?
 
What is your serving pressure for that length of line? or is it on the full 10Psi and using the flow control to serve?
 
Flow control taps add to the foaminess, try plain taps instead as the line balancing (line length) should set a good flow rate. Also if you want to run shorter lines then use 4mm ID line rather than 5mm.
 
I just let it carb at 10 PSI and serve at 10 PSI.

Try truning down teh pressure as the flow control under 10PSI pressure is causing additonal foam.

I can serve my beer on 20KPa ( 3psi ) no worries, serving at 120KPa has issues
 
You mentioned the tower doesnt have a fan. Temp plays a part, if the tower (including lines, taps) above the keezer are warm, it'll cause excessive foaming until they come down to 4C (or there abouts) which I suspect is a lot of beer running through the lines.

Chuck a font fan in and see if that helps?
 
it'll cause excessive foaming until they come down to 4C (or there abouts) which I suspect is a lot of beer running through the lines.

It's not terribly much beer, but it'll nearly all pour as foam and it IS quite a lot of foam.

If you're not fussy about "wasting" beer one perfectly reasonable solution is to keep a sacrificial glass near your taps, pour until it runs clean, then discard that and pour yourself a proper glass.
 
Good tips above. try them all. I like my beer well carbonated too and its as simple as turning down the serving pressure as mentioned when serving. Keep the keg connected to 12 psi when not serving or you can lose some carbonation if kegs are left at lower pressure. Pre serving you may need to release some pressure in the keg and serve slower at around 5-8 psi.
When your getting big foam and seems under carbed is serving to fast. The froth is carbonation released so the settled beer can seem flat. And cold as possible. As mentioned too it can be a warm tap will froth. Second glass poured is perfect because the tap is cold. That's why the pub taps are kept chilled with glycol. ;)
 
Thanks for all the replies.
I've turned the pressure down to around 7/8 and it seems a lot better. Next stop is a fan.

It also looks like I have a keg that is bringing air in from the liquid disconnect somehow. There is a fine stream of bubbles going through the lines even when filled with plain water. Tried new o-rings and lube but still getting it.
 
There have been reports of some of the new kegs sold today having pin holes in the dip tube and or the o ring under the top of the dip tube not sealing properly. This could explain the bubbles coming up the line even in water. I would be look at this.

As far as carbonation goes, if you have to turn your serving pressure down to pour, either your line is too short letting the beer come out too fast bashing into the glass causing foam, you have crud in your tap, your tap is crud, or more likely you are out of balance.
You want to be serving at the same pressure as what is required to hold the desired level of carbonation in your beer. Control the flow rate so it doesn't pour too fast by increasing the beer line length. (or a flow control tap with varying results). If you want the carbonation that 12psi gives you then 12psi is what you serve at. Leave your regulator alone.
 
i had ongoing foaming issues, beers would pour fine for a few glasses then after a happy period of a week or two would be constant battle with too much foam ect. i balanced and re-balanced my lines, still couldnt get it to pour consistently. suspected my KK Mk3 reg was creeping, swapped it out with a higher quality harris 601 and my pours are now much better and am far happier with how it all performs.
 
Most home brewers equipment is pretty simple so it comes down to knowing how to tune your own beers.
Its not easy. I'll have 3 kegs of different beers and different preferred carbonation levels. Home and mobile sometimes you just disconnect a beer that is overcarbed and let its own pressure pour itself. Just give it a small injection of Co2 to keep pouring it. So I am constantly shutting off manifold taps and adjusting the main reg. I need a better manifold though. Not the generic, they leak, including the check valves etc. A better higher shelf manifold. Any suggestions?
 
Most home brewers equipment is pretty simple so it comes down to knowing how to tune your own beers.
Its not easy. I'll have 3 kegs of different beers and different preferred carbonation levels. Home and mobile sometimes you just disconnect a beer that is overcarbed and let its own pressure pour itself. Just give it a small injection of Co2 to keep pouring it. So I am constantly shutting off manifold taps and adjusting the main reg. I need a better manifold though. Not the generic, they leak, including the check valves etc. A better higher shelf manifold. Any suggestions?

maybe a dual/triple reg with a line for each beer?


It's weird people will mash and ferment within a degree C precision but the regs people use have really coarse LP gauges that go to 1000+kpa and you're only using it around 75kpa, not to mention check valves that add "¬1-2psi". we should be aiming to use gas equipment that is as accurate as everything else in our brewing process.

TLDR:
Most home brew regs, guages etc are inaccurate AF. Keg land/king, sell us some decent quality LP 300kpa gauges.

edit: sprunk delling
 
So talking up to a six way manifold. Shut off taps etc.
For me its 4 for kegs, one for a long line for transferring, and all other easy co2 connect situations and one spare. Check valves, and no leakage, is a must! ?
 
Picture this:

An ice cold lager (XXXX, Carlton Draught, VB etc) poured at a pub in a schooner glass with an inch of head and bubbles that never stop rising off the bottom. That is how I want my beers to pour.

The beer that comes out of my taps have a lot more foam than needed and isn't very 'effervescent'.

I've been drinking beer for over 20 years and brewing for 6 or 7 years, but I still don't fully understand how carbonation, foam, head retention, serving pressure and carbonation pressure all play together when kegging.

It's mainly pale ales and IPA's on tap.

When I set up my keezer I used the carbonation charts and line calculator to work out if I aim for about 2.4vols at 4c I will need about 10 PSI and about 10 or 12 feet of 5mm line (can't remember exact length).
The taps are intertap flow controls on a tower without a fan. It is not only the first pour, but all pours that are like this.

Would simply increasing the line length help? Or do I need to reduce pressure?
How do I get the bubbles without the massive, dense foam head.

All lines and taps are cleaned and sanitized regularly.
I use one of these on the Fermzilla with only about 0.5m of beer line:
https://www.kegland.com.au/flow-control-ball-lock-disconnect-flow-restrictor-seconds.html
Working fine. Normally I use 4mm beer line of about 1.5m in length and between 10 and 12psi. Tap through fridge door in both cases.
 
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