Clever priming sugar required

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#1. I could set a lower spund pressure and physics suggests the o2 should be vented first.
Physics dictates the CO2 and O2 will mix in the headspace and you'll vent a mix of the two.

#3. Get it up to pressure and vent?
The more you vent, the more O2 you get rid of, and have CO2 from the beer replace it. You'll obviously need to add even more priming sugar
 
jof said: But, but, but...You know the current fad is for £££££ of dry hops and messing about with closed transfers otherwise it's too much oxygen and you ruin your expensive brew.

Hint: more traditional beer styles are available that are much less susceptible to oxidation.

Think of it this way. I am trying to make 2 stainless bottles of beer instead of 40.

Never in my mind was dry hopping or closed xfer. This is quite traditional.. I thought 👍😉
 
Another crazy option would be to try to force the O2 to get into solution as quick as possible so it can be consumed whilst the yeast is active, rather than letting it gently diffuse. Shaking it will do this (probably what happened when Peebee took his on a road trip). But oxygen refill still spoil beer quickly when in solution before it gets consumed.

And shaking a pressurised cornie seems risky thing to do 😂
 
Yeah, it will. But the hard part is trying to control it. If I remember when I had to do it, it was a process of venting some pressure and leaving it for a day or so, rinse and repeat. And in between, you need to decant some to check your progress. Can easily end up with no carbonation at all if you're not careful.
Surely that is the low pressure spundy's job? No faff. In my usual manner 🙂 I will come back when it's done.
 
Now you are talking my language 👍👍

So option #4 then. Gently shake not like a palm tree on a hurricane, after a couple of hours?
Genuinely, no idea. All I know is that the O2 will dissolve faster if you shake it. The more vigorous and longer you shake it, the larger the effect. I have no quantitative numbers, nor do I have any idea whether it'll benefit or hinder the beer. 🤷‍♂️
 
Personally I would never leave such a large headspace, I’m pretty sure the beer will spoil and I’m even more convinced after reading that it’s a hoppy ale.

If you decide you want to give it a try you absolutely need to purge the keg to minimise oxygen in the headspace.
 
Genuinely, no idea. All I know is that the O2 will dissolve faster if you shake it. The more vigorous and longer you shake it, the larger the effect. I have no quantitative numbers, nor do I have any idea whether it'll benefit or hinder the beer. 🤷‍♂️
I remember an Aussie brewer YouTube vid where he deliberately shook the bottles after bottling and adding priming sugar and comparing it with an unshaken bottle. The shaken bottle ended up a different colour (hoppy pale ale iirc) and showed all the signs of oxidation and tasted off. Admittedly that was after primary fermentation rather than at the end of it. 🤷‍♂️
 
You use the spunding valve to stop you over carbonating.
Not to remove carbonation after overdoing it !
Don't understand.
A PRV, just lets the excess pressure escape.

So surely it does both. If I create a lower pressure above the beer, the over pressure beer will release gas? No?
 
Just checking, the point of this exercise is to transfer beer from the fermenter to two (half filled) corny kegs and carbonate and dispense said beer without using bottled CO2?

If so…..
my complicated approach would be…

You will need a couple of gadgets (of course). A long length of beer hose with a beer quick connect at one end and a PLASTIC corny post (as these will accept both gas and beer quick connects) at the other. N.B. Ensure hose is long enough when connected between the cornys that corny #1 can be raised sufficient above corny #2 to create a syphon. In addition a short length of beer hose fitted with a gas quick connect at one end and a beer quick connect at the other. Something like this..

IMG_3151.jpeg

IMG_3152.jpeg

IMG_3153.jpeg

1. Harvest fermentation gas in milar balloons (at least 2) from primary fermentation of said beer, (N.B. Balloons need to be fitted with gas quick connects),
2. Prepare corny #1 by adding sugar solution and closing the lid,
3. Prepare corny #2 by closing lid and fitting a gas quick connect to it’s post,
4. Configure the connecting hose to have gas quick connect at one end and beer quick connect at the other, i.e. connect the beer quick connect on the short hose to the plastic post (see last pic).
5. Connect gas post of corny #1 to beer post of corny #2 to create a “daisy chain” of cornys ashock1
4. Transfer beer from fermenter to corny #1 through the beer post. Air should vent through gas post to corny #2 and then vent to atmosphere.
5. Transfer sufficient beer to fill to over-flowing corny #1 (no air) AND fill the pipe connecting the two kegs. Collect excess beer for later.
6. Disconnect the short and long hoses and disconnect beer quick connect from fermenter.

Corny #1 is now full of beer, no air. Connecting hose is full of beer. Corny #2 is still full of air.

7. Disconnect gas quick connect on short connecting hose from corny #1 reverse, and fit gas quick connect to plastic post on long hose (see second pic).
8. Raise corny #1 so base is above the top of corny #2.
9. Connect balloon to gas post on corny #1.
10. Connect beer quick connect on short hose to corny #1 beer post to start syphon, sucking fermentation gas into corny #1 and filling corny #2 with beer to expel all the air. N.B. A second balloon may/will be needed before corny #1 is full of gas and corny #2 is full of beer.

Corny #1 is now full of fermentation gas and corny #2 is full of beer (no air)

Are you sure you want to do this still? asad.

And finally…

11. Disconnect the partially empty balloon and connect to corny #2 gas post.
12. Connect the empty balloon to corny #1 gas post.
13. At this point you may need to fill the connecting hose with beer (from a jug used to collect overflow) to enable the beer in corny #2 to be syphoned back to corny #1.

No bottled gas needed but a right palaver! :coat:

I didn’t have anything else to do on this wet afternoon anyway 😂
 
Don't understand.
A PRV, just lets the excess pressure escape.

So surely it does both. If I create a lower pressure above the beer, the over pressure beer will release gas? No?
Why would you over carbonate the beer if you've got a spunding valve??
Yes, over prime to compensate for the excessive head space but set the spunding to the correct pressure for the temperature and target vol of CO2. ie about 7 to 8psi at 20°c for about 1.2 vol, Ideal for an ordinary bitter.
 
@Davegase yup get that.
I started this not knowing an awful lot about this. My knowledge was flat dispense, working to keep the gas out. Oh those happy days.....
I do now, from your links, know how to work out the required pressure. Then some smartass 😉😉started on about oxidisation which lead to venting. So need more fermentation gas fot that too now.

Just not sure how much priming sugar there needs to be to start with.

Which is pretty much where I started. I better understand it know and would like to get to a formulae.
Temp of beer & vols co2* & ammount of beer & amount of space = grams of priming sugar required

Getting there.

* wtf is vols of co2. Read 2 or 3 things now and still not sure. In English anyone?
I have decided for this beer its 2.2 for mathematical purposes but that's it 🤣
 
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@Davegase yup get that.
I started this not knowing an awful lot about this. My knowledge was flat dispense, working to keep the gas out. Oh those happy days.....
I do now, from your links, know how to work out the required pressure. Then some smartass 😉😉started on about oxidisation which lead to venting. So need more fermentation gas fot that too now.

Just not sure how much priming sugar there needs to be to start with.

Which is pretty much where I started. I better understand it know and would like to get to a formulae.
Temp of beer & vols co2* & ammount of beer & amount of space = grams of priming sugar required

Getting there.

* wtf is vols of co2. Read 2 or 3 things now and still not sure. In English anyone?
I have decided for this beer its 2.2 for mathematical purposes but that's it 🤣
I haven't got a formula but.
1.5 vol CO2 means that there would be 1.5 liters of dissolved CO2 in one liter of beer.
I think you said you were going to split a batch so that you had 11.5 litres each in 2 corny kegs.
Meaning you'd have about seven liters of headspace in each.
The brewing apps like brewfather do have priming calculators.
If I were going to try what you intend I would maybe double the amount given in the calculator.
Then set the spunding valve as per the carbonation calculators to achieve the required CO2 vol
at the temperature you are going to condition.
You could rig up a device with two gas disconnects some gas line at and a tee piece to connect both kegs to one spunding valve.
Doubling the priming sugar would also slightly increase the alcohol content, what a shame !
 
I'll try and run some numbers.
Using this carbonation chart, and a few assumptions.

So let's assume a 20L keg and you want that last bit of beer to be served at 0.333 atm. This would leave 20L of gas in the keg at 0.333 atm, which would be 20*1.333 = 26.6L of "uncompressed" gas.

If you want the beer to be served at a minimum of 1.5 volumes, then from the chart above that's about 1.8 volumes. So at a minimum, that's 18L of Co2 at standard pressure. All this will exit the keg with the beer, so it needs adding onto the above figure, giving 26.6+18 = 44.6L. Let's call it 45L.

Looking at the chart, 45L could be split into:
* 10L of beer at 2.7 volumes = 27L of CO2
* 2 volumes = 0.95atm pressure
* 10L of gas at 0.95 atm = 10*1.95 = 19.5L of uncompressed gas.
Which matches roughly the 45L minumin required.
So at a bare minumim, your 10L of beer in a 20L keg would be at 2.7 volumes and 0.95atm = 10psi.

But it's worse than that, because the first beer to be poured will have a higher volume of CO2 than the 1.5 volumes I estimated (it'll be 2.7 volumes) so you'll lose more CO2 from the keg, meaning you need more to begin with. So above the estimate of 2.7vol/10PSI is required.

So adding on a random fudge factor, you may be looking at 3-3.6 volumes of CO2 in your beer at the start, and 12-15PSI of serving pressure.

That's fizzy.
 
Using this
https://brewingcalculators.com/beer-line-length/

15 second pint pour and 0.5 m difference between keg centre and tap you'll need 5 metres of 4mm internal beer line.
3mm internal is 1.23 metres.
And I've proven that calculator to be inaccurate. There should be a discussion on there between me and the site owner. For my calculation and actual result, it was out by over 100%.

For a 12psi 10 second pour, it gave me 0.9m of 4mm ID hose. I'm actually using 2.5m.
 
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