is it necessary to inject co2 when kegging?

[Adri123]

Just kegged my first brew. I have bought an s30 bottle. Should I give it a squirt or leave it to the 85 grammes of sugar solution to do that?

TIA

Adri

 

[SloeBrewer]

The priming sugar will give you your initial pressure. Once the flow starts to slow on the tap (approx 2/3 full on the barrel), give it a squirt from the S30 bottle. Only give it a quick blast though (1 second or less), or you will freeze the bottle to the valve! If it needs more gas, wait for a minute, then give it a second shot.

 

[morethanworts]

I personally used to give it a blast anyway, with the lid partly screwed on, just to expel the air in the keg. Then turn the lid fully tight. The yeast doesn't need oxygen to ferment the priming sugar at this stage, only when it is growing.

It is the priming sugar that will make the fizz. (You'd get very little forced-carbonation if the keg has a pressure release valve, by the way, and I think it's only really in metal kegs that you'd do that).

 

[SloeBrewer]

The danger is you can over-pressurise the keg and cause it to leak out of the tap washer (did this on my first barrelled beer!).