Carbonation in unitank without carbstone

[philipsweden]

Hello all

I have a few questions regarding carbonation. We are starting a brewpub and would like some input on carbonation techniques based on our setup.

We do not have carbstones and can't install them on our tanks.

We do have spunding devices on the tanks and and use these as much as possible but we have to add some external CO2 on which I have a few questions. So these questions relate to the step after we have spunded the tank and cold crashed the beer.

Question 1:
I understand that a method of carbonating the beer fully is basically putting head pressure on the tank with a CO2 to the top of the tank and basically wait for the cold beer to absorb the CO2. We are trying this method and while I can assume this method would save some aroma it is a lengthy process.
Maybe someone can enlighten me on the carbonation charts. If my beer is 3 degrees C and I want say 2.6 volumes of CO2 in my beer the equilibrium pressure is something around 1 bar or (14PSI). Now I understand this is the equilibrium where no CO2 escapes the beer and no CO2 is absorbed by the beer? So if I would like the beer to absorb some CO2 at this temperature I would apply a higher pressure than now 1 bar and wait. Does a higher pressure always mean faster carbonation? Are there any charts available for carbonation levels together with a timeline of this? How long would you estimate this to take with a 4BBL (5HL) tank?

Question 2:
I have heard of some brewers that carbonate from the bottom of the uni-tank without a carbstone. You would open the valve very little and apply external CO2 that you allow to be pushed into the beer. I assume this process is faster that the one described above however with perhaps more loss of aroma? Does anyone have experience with this process and the pros and cons of it?
If I would try this method should I set my CO2 pressure to say 1.5 bar and then slowly bleed off some CO2 from the top of the tank?

Thank you very much for your help!

[mswebb]

You will be able to carb faster with a carb stone. If you can't put it in the tank, put it in an external loop. Beer out, carbed and put back in. There are manufactured devices that will do this or you can make your own with "T" fittings, sight glasses, a carb stone and a pump.

Check out HDP-Macdonald Steel or GW Kent for carb devices

[Surfmase]

You will be able to carb faster with a carb stone. If you can't put it in the tank, put it in an external loop. Beer out, carbed and put back in. There are manufactured devices that will do this or you can make your own with "T" fittings, sight glasses, a carb stone and a pump.

Check out HDP-Macdonald Steel or GW Kent for carb devices

I tried this a few times on my 1.5HL Unitanks. It can be done quickly (2 hrs), but there is a downside. I feed the external loop from the bottom outlet and return through the racking arm turned to the side. It always seems to stir up too much sediment. Maybe my crash isn't as effective as is should be, so now I spund, apply more head pressure, and wait it out.

[feinbera]

Maybe someone can enlighten me on the carbonation charts. If my beer is 3 degrees C and I want say 2.6 volumes of CO2 in my beer the equilibrium pressure is something around 1 bar or (14PSI). Now I understand this is the equilibrium where no CO2 escapes the beer and no CO2 is absorbed by the beer? So if I would like the beer to absorb some CO2 at this temperature I would apply a higher pressure than now 1 bar and wait.

The deal with the equilibrium charts is, at a given temperature (in your case, 3 °C), you need the given pressure of CO2 being pushed into the beer (1 bar) to perfectly balance out the given amount of CO2 already in the beer trying to get out (2.6 volumes). If you've got 1 bar on 3 °C beer that hasn't reached 2.6 volumes yet, you're not in equilibrium, and beer will continue to (sloooooowly) absorb CO2 until it reaches 2.6 volumes.

Something I've heard of people doing, but have never done myself, is to apply much greater pressure for a little while, to speed up the process (the farther out of equilibrium you are, the faster CO2 is absorbed/released). But it's a bit fiddly, as it's easy to overshoot or undershoot your carb level; you'd probably have to be committed to screwing up a few batches until you got the right pressure/time for your equipment dialed in.

[wailingguitar]

Bite the bullet and either have ports added to your tanks to accommodate carb stones, or get parts to set up a loop as was mentioned. Trying to gas with head pressure in a commercial environment will almost always result in a) running out of beer while waiting on the next one to carbonate and b) inconsistent carb levels in the beer you do serve.

[Jer]

If you fly me to Sweden I'll weld a ferrule on for you.....

Haha....you don't want me doing that, however, that is what you should be doing. Find a pro stainless welder that knows how to back gas, and be done with it. It'll cost you a few hundred bucks, but that's the most sensible solution. A beer out-beer in loop sounds like an infection waiting to happen to me, as well as ruining your naturally settled trub, yeast, and bound haze proteins.

Is there a way you could put a carb stone on a T on the bottom drain of your tanks??

I can't imagine not being able to spund to an adequate level of carbonation. With a variable PRV and an accurate gauge, you should be able to do it, provided your tanks are pressure rated for 15 or more PSI.

Do you have a brite tank, or all unitanks??

-J.

[grnis]

Hello all

I have a few questions regarding carbonation. We are starting a brewpub and would like some input on carbonation techniques based on our setup.

We do not have carbstones and can't install them on our tanks.

We do have spunding devices on the tanks and and use these as much as possible but we have to add some external CO2 on which I have a few questions. So these questions relate to the step after we have spunded the tank and cold crashed the beer.

Question 1:
I understand that a method of carbonating the beer fully is basically putting head pressure on the tank with a CO2 to the top of the tank and basically wait for the cold beer to absorb the CO2. We are trying this method and while I can assume this method would save some aroma it is a lengthy process.
Maybe someone can enlighten me on the carbonation charts. If my beer is 3 degrees C and I want say 2.6 volumes of CO2 in my beer the equilibrium pressure is something around 1 bar or (14PSI). Now I understand this is the equilibrium where no CO2 escapes the beer and no CO2 is absorbed by the beer? So if I would like the beer to absorb some CO2 at this temperature I would apply a higher pressure than now 1 bar and wait. Does a higher pressure always mean faster carbonation? Are there any charts available for carbonation levels together with a timeline of this? How long would you estimate this to take with a 4BBL (5HL) tank?

Question 2:
I have heard of some brewers that carbonate from the bottom of the uni-tank without a carbstone. You would open the valve very little and apply external CO2 that you allow to be pushed into the beer. I assume this process is faster that the one described above however with perhaps more loss of aroma? Does anyone have experience with this process and the pros and cons of it?
If I would try this method should I set my CO2 pressure to say 1.5 bar and then slowly bleed off some CO2 from the top of the tank?

Thank you very much for your help!

We cap the fermenters. Your should be equiped with a bunging apparatus. Otherwise. Blowing co2 from the bottom works fine and it's more sanitary than carbonation stones.

[adw1984]

Another option might be spunding. I was talking with a brewer out in Tennessee who would either cap at 4P from terminal or add head pressure, hitting about 25 psi. After that they would crash to 32F and end up around 2.5 volumes +/- 0.1 volumes. You just need a PRV that can handle the pressure.

[mswebb]

Another option might be spunding. I was talking with a brewer out in Tennessee who would either cap at 4P from terminal or add head pressure, hitting about 25 psi. After that they would crash to 32F and end up around 2.5 volumes +/- 0.1 volumes. You just need a PRV that can handle the pressure.

You also need a unitank that can handle the pressure. All of our fermenters are "unitanks" but are only rated to 15psi. Yes they have been tested to 30psi but I like to run my equipment within spec and set my prv's accordingly. My brite tank is similarly only rated to 15psi. Carb stone or loop is the way to go from a time perspective.

[Jer]

You also need a unitank that can handle the pressure. All of our fermenters are "unitanks" but are only rated to 15psi. Yes they have been tested to 30psi but I like to run my equipment within spec and set my prv's accordingly. My brite tank is similarly only rated to 15psi. Carb stone or loop is the way to go from a time perspective.

A rating of 15psi is more than enough, I've done it several times. It works great.

Get an adjustable PRV, but back it up with a 15PSI PRV.

While fermenting, set the adjustable PRV to keep your unitank at the PSI needed for your desired carbonatin at that temp.. Your beer is carbonated before it leaves the primary. I don't see how you can save any more time than that.

The adjustable PRV's can get bunged up, hence my STRONG suggestion to have a regular 15PSI PRV as a backup. No one likes a kaboom.

Spund on my friends. Spund on.

[Viridian]

Bite the bullet and either have ports added to your tanks to accommodate carb stones, or get parts to set up a loop as was mentioned. Trying to gas with head pressure in a commercial environment will almost always result in a) running out of beer while waiting on the next one to carbonate and b) inconsistent carb levels in the beer you do serve.

+1 to this.

There is no way that you should even consider carbonating without a stone. It will result in inconsistent carbonation levels and mouth-feel, coupled with unreliable carbonation times. Keep in mind that the size/design of the orifice pushing gas into solution matters. The smaller the orifice holes, the smaller the c02 bubbles, which result in usually a more preferred carbonation (smaller bubbles make smoother mouth-feel and less carbonic acid "bite"). This is a main benefit of carbonation stones and being able to pick the size of the stone, along with the flow rate / head pressure used.

[Jer]

+1 to this.

There is no way that you should even consider carbonating without a stone. It will result in inconsistent carbonation levels and mouth-feel, coupled with unreliable carbonation times. Keep in mind that the size/design of the orifice pushing gas into solution matters. The smaller the orifice holes, the smaller the c02 bubbles, which result in usually a more preferred carbonation (smaller bubbles make smoother mouth-feel and less carbonic acid "bite"). This is a main benefit of carbonation stones and being able to pick the size of the stone, along with the flow rate / head pressure used.

Well, sort of.

If you have a way to control how much of the co2 produced during fermentation is held in your unitank, then you don't need a stone, but if you bugger that up, you're screwed. Having a carb stone in place is a good idea as a backup.

In my limited experience, there are no finer bubbles than those made by yeast. Sooooo smooth.

[UnFermentable]

I'll throw in this as another imperfect option,

Buy more tanks....It helps with the time and will give you more space for product. Then you can wait until optimal levels are reached. May not be ideal for ales though, as the hop character will certainly die down over the required time.

As the others have said, you will take a long time to carb by head pressure only. Capping your tank earlier will help, however you risk keeping sulfur and other undesirables in the beer.

Adding higher pressure will help, but you will need to reduce the overage as you get closer to saturation. Otherwise you risk over carbing. I would suggest that if you are in fact able to reach a stable equilibrium at a given temperature and pressure, you will have very consistent carbonation from batch to batch. I have found this to be true with lagers that are tanked for a long period.

I still suggest the same as the others. Get a carb stone in any configuration. It's much better to be able to use it when needed than to wish you had it later.

Oh, and I like a rupture disk as opposed to another PRV, but just make sure you put a butterfly below it, in case you test its ability!

[Jer]

Oh, and I like a rupture disk as opposed to another PRV, but just make sure you put a butterfly below it, in case you test its ability!

Can you tell a rookie (that's currently shopping) why feel that way?? I know what the rupture disc is, but why is it better than a second PRV??

Thanks in advance...

-J.

[UnFermentable]

Can you tell a rookie (that's currently shopping) why feel that way?? I know what the rupture disc is, but why is it better than a second PRV??

Thanks in advance...

-J.

I like to know that there will be no leaks when spunding. The rupture disk is a seal, so it doesn't leak. I have had a few PRV's where the spring becomes weak, or junk gets clogged (if you have blow off) and that can cause a slow leak. Two PRV's is just doubling the chance of a leak IMHO. You might even consider putting the original PRV above the butterfly, and just switching to the rupture disk at capping time.

Also the rupture disk can be set for your safe maximum (say 25psi depending on your tank manufacturer) and then I can spund a little more gas (or a little sooner).