Priming A Keg With Sugar

[Nick JD]

I've been dragging the web for an hour now trying to find out how much sugar to use to get a "normal" carbonation in a 19L keg.

Everywhere seems to say, "half" what you'd use for bottles. Some say 2g/L and some say 6g/L ... bottling is ~8g/L isn't it?

Say I wanted 2.5 volumes (decent carb level), how much sucrose should I use?

And do I need to give the keg a few squirts of CO2 to seal the lid?

:icon_cheers:

 

[Hatchy]

I've been thinking about doing this as well. I'd suggest using co2 to seal the lid & to get the o2 out.

As far as how much sugar to use I've got no idea. I'm looking forward to seeing what other blokes say though.

 

[geoff_tewierik]

I have to ask why you're planning on priming the keg when you could just carb it with the CO2 you already have?

Priming the keg will lead to yeast being deposited in your glass when you pour a beer, due to the beer out drawing from the bottom of the keg, i.e. the middle of the dead yeast pile.

 

[schooey]

I've been dragging the web for an hour now trying to find out how much sugar to use to get a "normal" carbonation in a 19L keg.

Everywhere seems to say, "half" what you'd use for bottles. Some say 2g/L and some say 6g/L ... bottling is ~8g/L isn't it?

Say I wanted 2.5 volumes (decent carb level), how much sucrose should I use?

And do I need to give the keg a few squirts of CO2 to seal the lid?

:icon_cheers:

There is not a bad calculator here that I have used with success. As for purging with CO2, that seems to be a matter of opinion. As far as most of the learned people I have spoken to about it are concerned, any excess oxygen in the keg will soon be consumed by the yeast and replaced with CO2... I have done both and noticed no difference

 

[Nick JD]

I have to ask why you're planning on priming the keg when you could just carb it with the CO2 you already have?

I have to ask because it's for a portable keg with a keg charger for dispensation only. I'm aware that there will be yeast in it. I like yeast in some beers. Thank you for your input.

 

[Nick JD]

There is not a bad calculator here that I have used with success. As for purging with CO2, that seems to be a matter of opinion. As far as most of the learned people I have spoken to about it are concerned, any excess oxygen in the keg will soon be consumed by the yeast and replaced with CO2... I have done both and noticed no difference

That seems to be for bottles that calculator. I've read in a few places that kegs only need half the sugar for priming. Do you use that for keg priming?

I'm not concerned about oxygen in the keg (it'll be taken up by the yeast), but do I need a little bit of pressure to ensure the yeast-made CO2 doesn't leak out the lid before any pressure is built up?

 

[roller997]

That seems to be for bottles that calculator. I've read in a few places that kegs only need half the sugar for priming. Do you use that for keg priming?

I'm not concerned about oxygen in the keg (it'll be taken up by the yeast), but do I need a little bit of pressure to ensure the yeast-made CO2 doesn't leak out the lid before any pressure is built up?

In the past, when I bulk primed in the fermenter for bottling & kegging I had identical ratios of DME in the keg which might explain the higher carbonation in the keg dispensed beers. Mind you, they were easily fixed as it is easy enough to release a bit of pressure after the first sample if it is too highly carbonated.
A also checked with my Beersmith software and the software suggests that you use about 50% of the corn sugar in a keg than you use in bottles. This would mean for a beer that finished at 20 degrees, you would need 62 grams of corn sugar in a 19l keg as opposed to 125 grams for bottling.
I also prefer natural carbonation in kegs as I believe the takeup of oxygen and the slow creation of CO2 produce a better result.
In terms of not wanting a glass of yeast in your brew - You can always shorten the pickup tube, however like you I also like yeast in some of my beers.

Regards

Roland

 

[schooey]

Sorry....I fail to see the difference. The keg is just a bigger vessel, or bigger version of a bottle. Why would you only need half? When I bulk prime a batch, I often put half in bottles and half in a keg, never had a problem. Where I have had probles is bulk priming under attenuated beers, but that's not discriminative by bottle or keg either.

As for the kegs holding pressure, I don't have an issue there either. My lids pull up tight enough on the o-ring with the over centre latch to make a seal.

 

[TBird]

Coopers recommend 4 grams per litre.

 

[Phillbo]

I always sugar prime my kegs, 60g of sugar gives a low carbinated beer (how I like them), my beers are about six months old when I crack them, yeast in the first glass, clear as from then on. I also pressurize the keg to get a good seal after adding the sugar

 

[Nick JD]

I think I'll try 75g. Thanks all.

 

[barls]

i normally work out what it should be when bottling then half and use that amount in my kegs

 

[Barry]

I usually bulk prime a batch because I always bottle at least a few even if kegging. Usually don't have enough fridge space to get the keg cold and carbonated so priming it allows it be carbonated while warm. Then I put it in the fridge when I want to tap it, let it get cold, release pressure if necessary and serve. Bit yeasty the first glass or two but fine after that. Only have three fridges, one bar fridge and a kegerator. Usually 3 serving kegs in the kegerator but the rest are normally full of fermenting beer at different temps.

 

[Rotgut]

Whenever I do it I use 1/3 cup of dextrose with good results. Don't worry about yeast settlement, goes in the first 2 glasses.

 

[MarkBastard]

Most of my keg lids seal without pressure.

 

[bignath]

I'm glad Nick's asked this question because i have a few of those "commercial" 5L mini kegs i plan to use as camping beers and would love to know the answer..

I have also heard about only using half the amount of sugar that you would for a bottle, but can anyone explain why this would be the case??

And as a small deviation, i would assume by this logic that the closer your batch size gets from a keg to a bottle, the bigger the ratio of sugar to bulk prime?

If you consider a bottle to be 100% sugar for carbing, a 19L keg 50%, what would a 5L keg need?

Cheers and sorry for the slight dragging from Nick's OP

Nath

 

[pbrosnan]

I bulk prime in the fermenter. I usually bottle about 3 litres for samplers/competitions and keg the rest so as far as I'm concerned there's no distinction.

 

[fraser_john]

90gm in a keg seems to get pretty darn close to perfect in my set-up, usually it is a little under-carb'd, but I would prefer that than over carb'd.

 

[Hashie]

76 grams gets 2.4 volumes of CO2 in a 19 litre keg.

 

[katzke]

Sorry....I fail to see the difference. The keg is just a bigger vessel, or bigger version of a bottle. Why would you only need half? When I bulk prime a batch, I often put half in bottles and half in a keg, never had a problem. Where I have had probles is bulk priming under attenuated beers, but that's not discriminative by bottle or keg either.

As for the kegs holding pressure, I don't have an issue there either. My lids pull up tight enough on the o-ring with the over centre latch to make a seal.

I have also heard about only using half the amount of sugar that you would for a bottle, but can anyone explain why this would be the case??


Nath

Answer both at once.

Head space in percentage. I bet if you are a math whiz and calculate out the headspace, O2 consumed and replaced, and other factors you would find that bottles require more CO2.

As to why purge and seal the lid? Why not. Not all kegs are in great shape. The chance of flat beer is not worth it. There is more to sealing a keg then just the lid. If in doubt search posts on empty CO2 tanks.

For those asking why bulk prime a keg? I am sure there are many reasons. Just dont worry if you do not have to.