Accounting for existing carbonation when bottle conditioning

[DCBC]

Hi all,

I started kegging but recently brewed a Belgian blonde which I don't really want or need much of on tap. I have one keg free but would rather bottle the rest (the rest being 30ishL)

I am using a spunding valve at the moment, which is keeping about 3-5PSI in my kegmenter. The advantages of keeping the spunding valve on are:

1. To able to cold crash the beer nice and clear before I bottle without oxidation. I have bottled cold beer before and I've never had any problems with there being too little yeast in suspension, though the bottle conditioning process does take longer.
2. To help transfer the beer out to the bottles using a bottling gun, though I'm sure I will need some top up pressure from my gas bottle

My problem is that most carbonation calculators assume that the starting beer is flat, albeit they can correct for CO2 naturally dissolved at different temperatures. So is there any calculation you know about which will account for a starting level of calculation in the beer? Using this calculator, is it as simple as:

I want 2.8 vols, I calculate from the PSI that I already have x vols, (let's say x=1), so I only add enough dextrose to add another 1.8 vols?

Failing that, I guess the alternative is to cold crash with the spunding valve on, wait until it's completely chilled, release all pressure and give it several days for the beer to purge all the CO2 it's going to, and then bottle the cold beer.

Thanks in advance for your input!

 

[fury_tea]

I want 2.8 vols, I calculate from the PSI that I already have x vols, (let's say x=1), so I only add enough dextrose to add another 1.8 vols?

I can't offer much insight but I will say this is the approach I would take.

One thing to be weary of though is that straight dextrose could cause the beer to foam up like mad as it will provide nucleation points. I would be tempted to mix with a little water, then use a syringe to add a specified amount to your bottle, then purge and add your beer.

 

[DocAnna]

As with @fury_tea's comment your issue is likely to be foaming as there's already going to be a fair bit of carbonation. Personally I'd go with your calculations but also cold crash and bottle the beer cold with dextrose or dextrose syrup added first - if you are able to cold crash to 0 then you'll likely get away with the dextose dry but syrup is better. Your carbonation won't change with the reduced temperature as it's a sealed environment and the head pressure will reduce with chilling.

 

[RoomWithABrew]

I use a counter pressure bottle filler.
Beer at about 15 psi 4C,
Use this calculator and dextrose.
Works very well for several batches of Belgian beers targeting up to 4.5 vols.
Courtesy of @doug_293cz on us forum

 

[foxy]

Hi all,

I started kegging but recently brewed a Belgian blonde which I don't really want or need much of on tap. I have one keg free but would rather bottle the rest (the rest being 30ishL)

I am using a spunding valve at the moment, which is keeping about 3-5PSI in my kegmenter. The advantages of keeping the spunding valve on are:

1. To able to cold crash the beer nice and clear before I bottle without oxidation. I have bottled cold beer before and I've never had any problems with there being too little yeast in suspension, though the bottle conditioning process does take longer.
2. To help transfer the beer out to the bottles using a bottling gun, though I'm sure I will need some top up pressure from my gas bottle

My problem is that most carbonation calculators assume that the starting beer is flat, albeit they can correct for CO2 naturally dissolved at different temperatures. So is there any calculation you know about which will account for a starting level of calculation in the beer? Using this calculator, is it as simple as:

I want 2.8 vols, I calculate from the PSI that I already have x vols, (let's say x=1), so I only add enough dextrose to add another 1.8 vols?

Failing that, I guess the alternative is to cold crash with the spunding valve on, wait until it's completely chilled, release all pressure and give it several days for the beer to purge all the CO2 it's going to, and then bottle the cold beer.

Thanks in advance for your input!

The calculator you mentioned doesn't start at zero, it starts at 14.69 PSI or 1 ATM so depending on your cold crash temperature a certain amount of the CO2 will re-enter the beer, the colder the more CO2 gets dissolved back into the beer.
If you want to remove all the CO2 from your beer you will have to filter it.

 

[DCBC]

In haste, thanks so much everyone, I will read and reply when I'm back at my PC, but you've all given me a lot to think about (in a good way )