Set it and forget it method?

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sandog_au said:
Thanks for the info people,
My question was about applying a high pressure of CO2 to the keg then disconnecting and hopefully achieving carbonation. I know I can do it at low pressure and leaving the gas on. But I thought maybe if you pressurised the headspace of the keg the beer would slowly dissolve the CO2 until it reaches equilibrium and the required carbonation.
Cheers,
Sandy.
If you could apply about 500 psi to the head space there would be enough volume of gas to carbonate your beer if you disconnected straight away.

Not with just a squirt at 30psi though, this small amount will just be absorbed into the beer and still be basically flat.
 
pcmfisher said:
If you could apply about 500 psi to the head space there would be enough volume of gas to carbonate your beer if you disconnected straight away.

Not with just a squirt at 30psi though, this small amount will just be absorbed into the beer and still be basically flat.
Wear a bomb squad suit if you try it though :lol:
 
sandog_au said:
Thanks for the info people,
My question was about applying a high pressure of CO2 to the keg then disconnecting and hopefully achieving carbonation. I know I can do it at low pressure and leaving the gas on. But I thought maybe if you pressurised the headspace of the keg the beer would slowly dissolve the CO2 until it reaches equilibrium and the required carbonation.
Cheers,
Sandy.
The answer to your question is YES, that is what will happen. If you pressurise the headspace to a pressure, turn off the bottle and leave it (obviously providing your have no leaks in your gas line or keg seals), the beer will dissolve the CO2 to an equilibrium point.

The problem with the above is how do you predict the equilibrium that would be reached for a given beer temp, headspace volume, set pressure etc?

If the reason you want to do this way is because you are worried about leaks in your line, I would address the leaks before trying to do carbonation this way.

I did see a commercial brewery who were concerned about leaving a large cylinder (G size) turned on overnight with no atmospheric monitors, so they set they pressurised their conical to 100kPa overnight and then in the morning just set it to 100kPa again and turned the bottle off, they had worked out that doing this over 3 nights got them the level of carb they were after.
 
did see a commercial brewery who were concerned about leaving a large cylinder (G size) turned on overnight with no atmospheric monitors, so they set they pressurised their conical to 100kPa overnight and then in the morning just set it to 100kPa again and turned the bottle off, they had worked out that doing this over 3 nights got them the level of carb they were after.


Thats how I do it 40 - 50 psi for 1 min or till I hear the gas noise stop

I do this over 2 days 1 burst followed by another 2 hours later & then another 2 burst spaced out during the next day

I then set to 10-12 psi for serving & its ready to go on the 3rd day

Once its carbed & holding serving pressure I turn off at the tap just in case there is a leak
 
While thats ok, I prefer confidence in knowing there are no leaks. To be honest I'm still battling some!

Turning the bottle on and of also leads people to only slight crack the cylinder valve open. But this can actually cause a leaks out of the valve stem. Cylinder valves need to be opened fully so that the high pressure force is sent out the orifice it is designed to. Restricting it by semi opening the valve puts more pressure on the valve steam seal than its designed for and subsequently leaks!

One guy asked at my LHBS what the grey dial on the regulator was for. He had it wound in tight and was cracking the cylinder valve slightly until he got a tiny bit of flow. Surprised he hadnt popped the regulator safety valve and scared the shit out of himself yet...
 
sandog_au said:
Thanks for the info people,
My question was about applying a high pressure of CO2 to the keg then disconnecting and hopefully achieving carbonation. I know I can do it at low pressure and leaving the gas on. But I thought maybe if you pressurised the headspace of the keg the beer would slowly dissolve the CO2 until it reaches equilibrium and the required carbonation.
Cheers,
Sandy.
Hi Sandy,

You certainly could pressurise the keg to a certain pressure, disconnect it and in time it would be at the correct carbonation level but to know what this pressure is would involve working on a few variables, mainly head space and temperature. You would probably have to get special pressure vessels as I imagine this pressure would be far beyond what a keg could handle.

We have dabbled with this in the warehouse and started playing around with load cells. The idea was that you could easily calculate the mass of CO2 that your set volume of beer needed. You would enter this mass into the load cell controller and then set the CO2 pressure to the maximum that the keg could handle. As the keg slowly gets heavier and heavier and finally reached the set value it would shut off a valve and stop any more CO2 from entering the keg. We got the load cells in and then that was about it until we got distracted with another project!

Always too much going on over here!
 
It's easier to just get decent disconnects etc, set to your pouring pressure 10-14psi, and forget it for a week. Then you have an excellent beer every every time with no need for extra pressure tanks etc.
 
QldKev said:
It's easier to just get decent disconnects etc, set to your pouring pressure 10-14psi, and forget it for a week. Then you have an excellent beer every every time with no need for extra pressure tanks etc.
Thats the best advice and your beer will love you for it. No need to overcomplicate it. Balance your system and dont touch the regulator ever just hook up to gas. Beer clears as it carbs. Easy peasy. Best thing i ever did was get rid of my john guest fittings. Pretty sure john owns the c02 factory.
 
Call me old school.
It's not like I don't have the CO2 to carb my kegs, I just love the simplicity of adding the measured grams of dextrose to each keg as I fill it. After that it just looks after itself. It does take some more time however. I treat all my kegs with dextrose for carbonation, except if time does not permit.

I like that too because I vary the carbonation level per beer style. So that is just + - 10g of Dextrose.

Steve
 
Brewman_ said:
Call me old school.
It's not like I don't have the CO2 to carb my kegs, I just love the simplicity of adding the measured grams of dextrose to each keg as I fill it. After that it just looks after itself. It does take some more time however. I treat all my kegs with dextrose for carbonation, except if time does not permit.

I like that too because I vary the carbonation level per beer style. So that is just + - 10g of Dextrose.

Steve
Devils Avocado here, but does anyone know how much alcohol and any unfermented gravity points a standard prime introduces to a beer?
 
Spiesy said:
Devils Avocado here, but does anyone know how much alcohol and any unfermented gravity points a standard prime introduces to a beer?
I like avocado, not in beer though..
So the Dextrose addition I make to my kegs adds about 0.2 to 0.3% to the alc/vol. In Brewbuilder I just add that into the recipe the grams of dextrose I add and noted the change in % Alcohol.



Good question.


Cheers Steve
 
Brewman_ said:
I like avocado, not in beer though..
So the Dextrose addition I make to my kegs adds about 0.2 to 0.3% to the alc/vol. In Brewbuilder I just add that into the recipe the grams of dextrose I add and noted the change in % Alcohol.



Good question.


Cheers Steve
Thanks for the answer. That's a really small percentage shift. Inconsequential, I guess.
 
If you bulk prime the keg, do you find you end up with much secondary fermentation yeast settled out when its finished?
 
Yeah, it does make a difference.

Which is I guess your question. It's not a big difference to me. My normal brewing process varies more than that to be honest.
 
Mr B said:
If you bulk prime the keg, do you find you end up with much secondary fermentation yeast settled out when its finished?
Nope. I find no difference. I thought that too.

I always get some settling, the first beers are cloudy, but providing the fermentation is complete, and in line with your normal process, the amount of settling will be similar to a forced carb.

I've done the same with a fully filtered keg and they pour clear from the start. I just don't filter these days.
 
Brewman_ said:
I like avocado, not in beer though..
So the Dextrose addition I make to my kegs adds about 0.2 to 0.3% to the alc/vol. In Brewbuilder I just add that into the recipe the grams of dextrose I add and noted the change in % Alcohol.



Good question.


Cheers Steve
Thats about the same amount bottle priming adds. But you add considerably less sugar/dextrose to kegs to naturally carbonate from memory. Hows that work?
 
QldKev said:
It's easier to just get decent disconnects etc, set to your pouring pressure 10-14psi, and forget it for a week. Then you have an excellent beer every every time with no need for extra pressure tanks etc.
Same here.
Works everytime. Patience is a virtue.
 
DJ_L3ThAL said:
Thats about the same amount bottle priming adds. But you add considerably less sugar/dextrose to kegs to naturally carbonate from memory. Hows that work?
That's my keg priming numbers. Not bottles.

I find it works to treat them just the same.

You might want to tweak things here and there, but I reckon you'll find its OK.
 
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