Stout Carbonation (Keg)

[Audard]

Hi everyone,

First time poster here (from what i can remember).
Recently made the jump to kegging with the help of friends with parts and setup.
My first keg is a stout (7%) and to get it running i asked my LHBS the in's and out's
They recommended 40PSI for 36hrs then drop the pressure down to about 6PSI for serving.
I carbonated through the IN line (they recommended the OUT but i choose not too this time) at 40 PSI for 36hrs.
Burped the keg and dropped the pressure down to 6PSI and gave it a pour... it was mainly head and i could hear gas fizzing out the tap head as i poured.
If i let the beer trickle in the head is reduced and beer starts to form from the foam.
My question, is the beer under or over-carbonated?
Since i carbed through the IN line i would assume that the beer has not carbed as quick as going through the OUT line.
I've also read that you need a serving pressure of around 25-30 PSI for a stout but that sounds like if you are using a beer mix with nitro and an official stout tap.

 

[laxation]

This guide shows you how much carb is correct: http://www.kegerators.com/carbonation-table.php
30psi is ridiculous for co2, but i have no idea about nitro.
I've never carbed a keg like how you were instructed though so I'm not of any more help! I just leave the keg at serving pressure for a week so I don't screw it up

 

[Audard]

I just leave the keg at serving pressure for a week so I don't screw it up

I need to follow up with the LHBS today but i am somewhat regretting this method.

 

[laxation]

You'll be fine! If it is overcarbed, just take it off gas and let the pressure out, shake it up a bit, let the pressure out again.
Do this a few times over a day or so and then try again!

There's nothing wrong with how you did it, but I think it's maybe a bit more trial and error until you find out what works. Eg. it might be 36psi for 24 hours

Can also check this to see if your lines are the right size: http://www.mikesoltys.com/2012/09/17/determining-proper-hose-length-for-your-kegerator/

I'm very much just starting out myself, but recently I went through a whole heap of things trying to figure out why my kegs were overcarbed. Eventually it turned out it was the temperature was fluctuating too much in the old fridge, so you can consider that too, although we probably don't have the same problem...

 

[Audard]

The fridge i am using is pretty old but it does seem to hold the temperature steady.
I will have to look into the line length and do some other tests.
Right now i am unsure if it is over-carbonated.
Is there a sure way to tell if your keg is?

 

[good4whatAlesU]

Line length was my issue when setting up my kegging system.

Nowadays like lax I just 'set and forget' at serving psi for a week to reduce stuff ups. You can still give the keg a shake the first couple days using set and forget to speed things up a bit.

 

[Yob]

I serve my stouts on co2, 15-20 psi and through a sparkler, like nitro in the way it settles but without the **** taste that I seem to get from nitro stouts

 

[laxation]

Right now i am unsure if it is over-carbonated.
Is there a sure way to tell if your keg is?

Eliminate potential problems 1 by 1 until you figure it out I guess..

Here's my thread with a bunch of ideas http://aussiehomebrewer.com/topic/95045-diagnosing-over-carbonation-problem-in-keg/

 

[2cranky]

I do 50psi for 24 hours at 2c. Then let all or most pressure out and reset to my serving at 8psi.
Some beers pour right from the get go but others need to settle down for 24 hours.

 

[Topher]

If you carb at high pressure.... absolutely make sure your lines are securely clamped on to your fittings.
A blowout at that pressure is a spectacular way to cover your room in beer.

 

[manticle]

I find 120 kpa for about 20 - 24 hrs at around 10 deg C gets my stouts to where I want them. Other beers that get a bit more fizz will be 120 for 30- 40 hrs. That converts to less than half the pressure you were recommended and while I don't like super fizzy (or super cold), my guess is you're overcarbed.

 

[Audard]

Cheers for the advice everyone.
Clamps are tighter then my wives wallet.
Going to let the keg rest for 24hrs then retry a few things.
I will post back with my "pourings" later.

 

[2cranky]

If you carb at high pressure.... absolutely make sure your lines are securely clamped on to your fittings.
A blowout at that pressure is a spectacular way to cover your room in beer.

YES - I turn all the other lines off at the manifold.
The kegs I'm carbing don't have taps connected.
50 psi will almost definitely blow my picnic taps off the lines. Not that I have done it. :lol:
Lube on your gas disconnects will ensure a good lock on as well.

 

[mr_wibble]

I carbonated through at 40 PSI (276 kPa) for 36hrs.
Burped the keg and dropped the pressure down to 6PSI (41 kPa) and gave it a pour... it was mainly head and i could hear gas fizzing out the tap head as i poured.
If i let the beer trickle in the head is reduced and beer starts to form from the foam.
My question, is the beer under or over-carbonated?

276 kPa / 40 PSI for 36 hours is not a lot in my experience. The problem is that you're wishing the gas would dissolve into the liquid, but it's just sitting there in the cavity at the top of the keg. The idea of putting it in through the OUT post is that at least it bubbles up through the beer, helping it dissolve. Also the CO2 dissolves into your beer much more readily at lower temperatures. So if you started with a room-temp keg, it needs time to cool before much happens with the gas.

If you search for the "Ross Method" on this forum, there's a wealth of information on force-carbing kegs quickly.
But the executive summary is: Pressure up high, gently rock the keg to help the gas dissolve. As you rock the keg, you will hear your regulator "groan" as the gas continually dissolves into the liquid. Compare this with just hooking it up sitting there - it groans only until the head-space is pressurised - this then slowly seeps into the liquid.

So you left your keg at high pressure for a while, burped it, and then immediately served it? I would think the beer is still carbonated at high pressure - it would need some time to equalise, and come back down to serving pressure.

How long is the tube between your keg and tap? The idea is that the flow-restriction of the tubing "uses up" the pressure behind the beer, you only want a small amount of pressure left at the tap. I use "Valpar" beverage tubing (from the LHBS), which is 5mm _inside_ diameter. About 3 metres of this is enough to handle a serving pressure of 70kPa (10PSI). You can't compare serving pressures unless the tubing size is the same. There is line length calculator spreadsheet here. If you do not want to have all the tubing, you can also go for taps with an extra flow restriction handle. These can fix the pressure without the need of the extra tube, but cost more.

Other things (besides over-carbing) that can cause foaming -
- hot taps
- not fully opening the tap
- dirty and/or old (rough) glassware (lots of nucleation points for bubbles: google "mentos coke fountain")
- Pouring directly into the bottom of the glass for the whole pour.

So - what to do...
My best guess is that you need to wait a while for the bit of excess gas to leave your beer (after a high-pressure fast-carb'). You may need to burp it again.
This is why carbonating at serving pressure is easy - it removes a couple of variables from the process. You know your beer definitely isn't over-carb'ed.

Otherwise: Check your beer-tap to keg line-length. If your LHBS set this up, this should be OK, but generally (with 5mm line) about 3 metres is needed.
If your taps are hot the first half of the first pour will foam.
Pour the first part onto the side of the glass, and then depending on how much head you get/want, pour straight into the bottom.



EDIT: Clarification on Line Length && Serving Pressure:
I guess I rabbited-on a bit in this post (Me? Rabbit on about beer stuff!? Surely not!)

It's not complicated, but the whole point is that you need to balance whatever serving pressure you use with the type and amount of tubing you have. So if you use a lower serving pressure, you can use less tube. (gravity also comes into play to a certain extent, but really only if you're serving up from a cellar).

 

[mr_wibble]

I serve my stouts on co2, 15-20 psi and through a sparkler, like nitro in the way it settles but without the **** taste that I seem to get from nitro stouts

What does that "**** taste", taste like?
The nitro doesn't have the sting of CO2, but i reckon that's more of a texture/mouth-feel thing.

Next time you're heading south, PM me. I wanna know if my nitro stout has it too

 

[manticle]

South?

 

[Grott]

I find 120 kpa for about 20 - 24 hrs at around 19 deg C gets my stouts to where I want them. Other beers that get a bit more fizz will be 120 for 30- 40 hrs. That converts to less than half the pressure you were recommended and while I don't like super fizzy (or super cold), my guess is you're overcarbed.

Do you carbonate ales at 19 deg C? I note you mentioned before you don't like fully carbonated brews so at what volume of co2 do you like and temp for consumption as wouldn't mind a try myself.

 

[manticle]

Sorry typo. 10 deg.

As for vol - I don't really calculate for kegs but when I bottled, I generally preferred 1.8 - 2, somewhat style dependent.

And I should add it mostly starts at 1-2 deg C because i's just come out of the cc fridge.

 

[Audard]

276 kPa / 40 PSI for 36 hours is not a lot in my experience. The problem is that you're wishing the gas would dissolve into the liquid, but it's just sitting there in the cavity at the top of the keg. The idea of putting it in through the OUT post is that at least it bubbles up through the beer, helping it dissolve. Also the CO2 dissolves into your beer much more readily at lower temperatures. So if you started with a room-temp keg, it needs time to cool before much happens with the gas.

If you search for the "Ross Method" on this forum, there's a wealth of information on force-carbing kegs quickly.
But the executive summary is: Pressure up high, gently rock the keg to help the gas dissolve. As you rock the keg, you will hear your regulator "groan" as the gas continually dissolves into the liquid. Compare this with just hooking it up sitting there - it groans only until the head-space is pressurised - this then slowly seeps into the liquid.

So you left your keg at high pressure for a while, burped it, and then immediately served it? I would think the beer is still carbonated at high pressure - it would need some time to equalise, and come back down to serving pressure.

How long is the tube between your keg and tap? The idea is that the flow-restriction of the tubing "uses up" the pressure behind the beer, you only want a small amount of pressure left at the tap. I use "Valpar" beverage tubing (from the LHBS), which is 5mm _inside_ diameter. About 3 metres of this is enough to handle a serving pressure of 70kPa (10PSI). You can't compare serving pressures unless the tubing size is the same. There is line length calculator spreadsheet here. If you do not want to have all the tubing, you can also go for taps with an extra flow restriction handle. These can fix the pressure without the need of the extra tube, but cost more.

Other things (besides over-carbing) that can cause foaming -
- hot taps
- not fully opening the tap
- dirty and/or old (rough) glassware (lots of nucleation points for bubbles: google "mentos coke fountain")
- Pouring directly into the bottom of the glass for the whole pour.

So - what to do...
My best guess is that you need to wait a while for the bit of excess gas to leave your beer (after a high-pressure fast-carb'). You may need to burp it again.
This is why carbonating at serving pressure is easy - it removes a couple of variables from the process. You know your beer definitely isn't over-carb'ed.

Otherwise: Check your beer-tap to keg line-length. If your LHBS set this up, this should be OK, but generally (with 5mm line) about 3 metres is needed.
If your taps are hot the first half of the first pour will foam.
Pour the first part onto the side of the glass, and then depending on how much head you get/want, pour straight into the bottom.



EDIT: Clarification on Line Length && Serving Pressure:
I guess I rabbited-on a bit in this post (Me? Rabbit on about beer stuff!? Surely not!)

It's not complicated, but the whole point is that you need to balance whatever serving pressure you use with the type and amount of tubing you have. So if you use a lower serving pressure, you can use less tube. (gravity also comes into play to a certain extent, but really only if you're serving up from a cellar).

Cheers for the awesome reply.
The first thing that I wasn't doing was opening the tap head fully...even then the first few seconds where foaming before the pour would balance out.
My line is 2 meters (was recommended).
It seems to pour rather decent now except for the first few seconds each time.
I have turned off the gas and burped it. I will let it sit until tonight and turn it back on to server pressure and see how it goes.
I will need to sit down this weeendk and measure everything accordingly and do a proper calculation to understand my setup fully instead of listening to HALF the information i require.