Another of my lame carbonation threads!

[jdlev]

I am wondering if I have my tap setup wrong. The beer is never at a steady carbonation. It's either all foam or almost completely flat. The carbonation bounces around over the life of the keg. So far...here's what I've done:

1) Let sit for about 10 days at 7psi using the slow carb method. Tried a few, and they were darn near flat.
2) Decided to do a shake and bake, so I took the keg out, and rolled it around at about 25psi...all foam
3) Took it to the beach, and dunked it in a sink of ice water. Still all foam.
4) Ran out of ice, so the keg sat for 2 days and warmed up...then we took it home.
5) Finally got a perfect pour after hooking it back up to my tap system. 16oz glass and 1" of head.
6) Go back for seconds, and it's FLAT!!!
7) Shake and bake, rd 2. And we're back to all foam.

Why the heck can't I get a consistent carbonation? Could it be temperature changes? Could it be my tap is f'd up? It looks like liquid in the line, and then when you pour it, it comes out pure foam? Maybe my keg has a slow leak...but I can't hear any CO2 heading into the tank to replace any type of leak? Thanks for any advice..

 

[MikeRoBrew1]

Disclaimer, I am no expert. I have found that for me personally, a combination of the techniques gives me pretty good carbonation level.

First I give the keg a MILD force carb by pressurizing to 30-40psi and shaking for just a few minutes. I don't roll the keg around or shake it violently. Just keep it upright and shake back and forth; as long as you can hear the gas going in you are shaking plenty hard.

After this you must wait at least a few hours before serving, but it still won't be completely carbonated yet. I leave the pressure up in the 30-40 psi range for a couple days.

Then I lower the pressure to 12-15psi for another few days-week. By this time I an usually drinking the keg. After a week or so the keg will start to get over-carbonated and a glass will be about half foam.

At this point I lower the pressure to about 4-6psi; the lower pressure helps prevent overfoaming even if the beer is a tad overcarbonated. After another week at low pressure you may have to bump it up a notch but it's been fine for me. My kegs are gone in about 2-2.5 weeks on tap.

Normally I just rack into the keg from the primary fermenter after a month. Toss it right in the fridge and carb and start drinkin ASAP. Now I have a couple extra kegs so I am starting to condition longer but I am starting to research the effects of carbonating and conditioning kegs warm vs. cold.

This is my current method and I've only had my kegs 6mo or so at the most.

 

[WrongCoastBrewery]

I would suggest you look at some CO2 saturation tables and figure out for a given temperature, how much CO2 pressure you would need for a specific volume of CO2 in your beer. There is a good thread on this in the kegging tab:

https://www.homebrewtalk.com/f35/keg-force-carbing-methods-illustrated-73328/

But if you are going to do the set it and forget it method, why not use priming sugar. Beersmith has a priming sugar calculator that will adjust for kegs. I would suggest that instead since it wastes less CO2.

 

[jdlev]

I would suggest you look at some CO2 saturation tables and figure out for a given temperature, how much CO2 pressure you would need for a specific volume of CO2 in your beer. There is a good thread on this in the kegging tab:

https://www.homebrewtalk.com/f35/keg-force-carbing-methods-illustrated-73328/

But if you are going to do the set it and forget it method, why not use priming sugar. Beersmith has a priming sugar calculator that will adjust for kegs. I would suggest that instead since it wastes less CO2.

Here's the weird thing...even when all i get is a giant glass of foam, when it finally settles, the beer itself is flat. Isn't that strange?

 

[robbiex0r]

When you were sitting at 7psi, what was the temperature of the beer?

 

[Yooper]

Here's the weird thing...even when all i get is a giant glass of foam, when it finally settles, the beer itself is flat. Isn't that strange?

Not at all. The foam is the co2 "knocked out" of the beer. So, you get foam (the co2) but the beer left is flat. It's the way it is.

One thing that can help is to just leave the beer alone. The problem is that shaking/warming/chilling/shaking all affects the carbonation level. For example, take a warm coke and shake it. Then open it. Even though the coke is perfectly carbed from the fridge, the warming and shaking will dislodge the co2 and send it spraying all over the place.

Changing the psi in the keg will change it, too, of course. So, if the beer is sort of flat at 7 psi, turning it up to 11 psi may solve the problem. No shaking, warming, etc.

There are carbonation tables out there, as carbonation is a function of co2 pressure and temperature. For my system, my kegerator is 40 degrees and my regulator is set at 12 psi. If the keg gets warm when I take it to a picnic, it has to be chilled before it's "right" again.

 

[VictimKBrew]

+1 to Yoop. That explanation helped. I just bought a dual tap kegerator last week and have been struggling to grasp CO2, volumes of CO2, PSI, head space, etc. I was hoping you could just hook it up and go. I got a lot to learn.

 

[jdlev]

When you were sitting at 7psi, what was the temperature of the beer?

I have no idea

 

[jdlev]

Not at all. The foam is the co2 "knocked out" of the beer. So, you get foam (the co2) but the beer left is flat. It's the way it is.

One thing that can help is to just leave the beer alone. The problem is that shaking/warming/chilling/shaking all affects the carbonation level. For example, take a warm coke and shake it. Then open it. Even though the coke is perfectly carbed from the fridge, the warming and shaking will dislodge the co2 and send it spraying all over the place.

Changing the psi in the keg will change it, too, of course. So, if the beer is sort of flat at 7 psi, turning it up to 11 psi may solve the problem. No shaking, warming, etc.

There are carbonation tables out there, as carbonation is a function of co2 pressure and temperature. For my system, my kegerator is 40 degrees and my regulator is set at 12 psi. If the keg gets warm when I take it to a picnic, it has to be chilled before it's "right" again.

Thanks for the advice Yoop...I'll pay closer attention to those tables and temperature :rockin:

 

[akthor]

7 psi is too low for set and forget method. Like yoop said 12 psi seems to be the magic number for most folks. My fridge is 38 - 39 and I have it at 12psi and the beer is carbed at about 2 weeks time though 3 weeks + is perfect.

I have done the force carbing with 36 hrs at 30 psi then 5-7 days at 12psi etc. and yeah it was carbed and drinkable but there is a big difference in mouthfeel and saturation when done at 12 psi for 2 or 3 weeks. Not to mention the added time of 2 or 3 weeks conditioning in the keg improves everything else, taste, clarity ect.

You read it everywhere on here whether it's how long you primary, secondary, force carb or bottle condition. TIME rules all. If you try to rush any part of the process you are going to be SACRIFICING something. It's like physics, for every action there is a reaction. So yes you can skip steps, you can rush things, and you will get beer and beer that is drinkable. Will it be as good as the same beer if you had followed all the steps and waited the proper amount of time??? Ummmm HELL NO

 

[jdlev]

7 psi is too low for set and forget method. Like yoop said 12 psi seems to be the magic number for most folks. My fridge is 38 - 39 and I have it at 12psi and the beer is carbed at about 2 weeks time though 3 weeks + is perfect.

I have done the force carbing with 36 hrs at 30 psi then 5-7 days at 12psi etc. and yeah it was carbed and drinkable but there is a big difference in mouthfeel and saturation when done at 12 psi for 2 or 3 weeks. Not to mention the added time of 2 or 3 weeks conditioning in the keg improves everything else, taste, clarity ect.

You read it everywhere on here whether it's how long you primary, secondary, force carb or bottle condition. TIME rules all. If you try to rush any part of the process you are going to be SACRIFICING something. It's like physics, for every action there is a reaction. So yes you can skip steps, you can rush things, and you will get beer and beer that is drinkable. Will it be as good as the same beer if you had followed all the steps and waited the proper amount of time??? Ummmm HELL NO

I learned that lesson well after my first batch. Now I just make on average 3-4 batches a month, and all is well

BTW...this chart was a huge help in determining the problem. It's amazing how much CO2 psi must be increased to compensate for temperature rise.

http://www.kegerators.com/carbonation-table.php

 

[Chemkrafty]

I am wondering if I have my tap setup wrong. The beer is never at a steady carbonation. It's either all foam or almost completely flat. The carbonation bounces around over the life of the keg. So far...here's what I've done:

1) Let sit for about 10 days at 7psi using the slow carb method. Tried a few, and they were darn near flat.
2) Decided to do a shake and bake, so I took the keg out, and rolled it around at about 25psi...all foam
3) Took it to the beach, and dunked it in a sink of ice water. Still all foam.
4) Ran out of ice, so the keg sat for 2 days and warmed up...then we took it home.
5) Finally got a perfect pour after hooking it back up to my tap system. 16oz glass and 1" of head.
6) Go back for seconds, and it's FLAT!!!
7) Shake and bake, rd 2. And we're back to all foam.

Why the heck can't I get a consistent carbonation? Could it be temperature changes? Could it be my tap is f'd up? It looks like liquid in the line, and then when you pour it, it comes out pure foam? Maybe my keg has a slow leak...but I can't hear any CO2 heading into the tank to replace any type of leak? Thanks for any advice..

Let's take this one at a time...

1) In general, for beer stored at 38F, you are going to want the pressure set around 12-13 psi. The tables that people are referencing can get you even more control.

2) I would recommend waiting at least 12 hours (preferably 24) before serving after doing a shake method. Even using the shake method, I would not raise the psi over your target pressure (12 psi). If you do, you run the risk of overcarbing your beer and pouring foam until you can purge the excess dissolved CO2.

3) Not sure...not enough info to really diagnose. Probably overcarbed or shaken up from the transportation. Could also be warm beer lines.

4) N/A

5-6) I'm guessing you had flat beer and the warmth of the beer or lines contributed to the "foamy" pour. It appeared to be perfect, but since the beer itself was flat, no good.

7) It needs to rest.

Conclusion

There are two main variables when dealing with dispensing: Temp and pressure. Keep the temperature on target for not only the beer, but the lines you are serving from. Warm lines can cause foam as easily as warm beer.

Keep the pressure on target. Don't be shaking the CO2 out of solution. Don't over or under pressurize. Avoid "shake and bake" until you figure out your system.

Third (also dealing with pressure), you need to balance your system. Assuming you are using 3/16" line and setting your pressure at 12 psi, you need to have approximately 5 ft of beer line to balance your system and not produce foam. One thing you can do is start with 8 ft of hose and trim it back until it pours the way you want. Just make sure the temp and pressure are correct before doing this.