Pressure barrel: trying to early?

[HighlanderPorc]

Hello everyone.

I transferred my brew from the fermentation vessel to my King Keg, adding 85g of spraymalt for priming. I plan to leave for at least two weeks. I did however try a very small glass after 24 hours, just to check that pressure was building correctly. All seemed fine but my question is: in trying a small sample, will I have negatively affected the two week process? Obviously some CO2 will have escaped but I’m hoping not enough to really affect the internal pressure. Am I right in thinking it will continue to produce CO2 for a little while anyway since I doubt the yeast will have completely finished off the spraymalt?
Thanks for your help in advance.
NB I’m very aware having read a lot about pressure barrels that they are prone to plenty of issues! Eventually I’m sure I’ll move over to cornies since it seems they’re more reliable but I’ll give it a go in the PB for now!

 

[hotbeer]

Unless your sample was a major percentage of the beer volume in the pressure barrel, I doubt you made an impact on it.

You did get your sample from a tap and not have to open the barrel letting out all the pressure inside, didn't you?

What are your plans to keep it pressurized after you do start drawing beers for everyone from it?

 

[HighlanderPorc]

Hi there- thanks for the reply. Yes from the tap (I replaced the standard tap with a sparkler tap). It was probably around 150ml (0.32 pints).
Re keeping it pressurised, unless there are leaks, the consensus seems to be that it will hold carbonation until around a half full and I’ll top up manually with CO2 through the valve.
PS just noticed the typo in the title. Awful!

 

[VikeMan]

Re keeping it pressurised, unless there are leaks, the consensus seems to be that it will hold carbonation until around a half full and I’ll top up manually with CO2 through the valve.

The beer will have carbonation until the last of the beer is gone. But it will have less and less volumes of CO2 per volume of beer as the headspace gets bigger. This starts as soon as the first pint (or whatever) is poured. I only mention this because "half full" sounds like there's some sort of step function here. There isn't.

 

[cire]

The beer will have carbonation until the last of the beer is gone. But it will have less and less volumes of CO2 per volume of beer as the headspace gets bigger. This starts as soon as the first pint (or whatever) is poured. I only mention this because "half full" sounds like there's some sort of step function here. There isn't.

There are two types of King Keg. Both, intended for ales, rely mainly on natural carbonation. They are fitted with an S30 valve for CO2 addition should the pressure drop too low. One version has a bottom top, but another has a top tap with take-off from a float requiring a positive pressure to raise the beer. When such a King Keg is half full of beer, the take-off point will be about 6 inches below the tap and while half a psi is enough to carbonate a British style beer, it won't be sufficient to raise and dispense a decent looking pint of ale.

 

[VikeMan]

There are two types of King Keg. Both, intended for ales, rely mainly on natural carbonation. They are fitted with an S30 valve for CO2 addition should the pressure drop too low. One version has a bottom top, but another has a top tap with take-off from a float requiring a positive pressure to raise the beer. When such a King Keg is half full of beer, the take-off point will be about 6 inches below the tap and while half a psi is enough to carbonate a British style beer, it won't be sufficient to raise and dispense a decent looking pint of ale.

Ok. I'm not sure why you addressed that to me, though. My point was that there's no magical breakpoint at "half full," and that the decrease in CO2 volumes in the beer is continuous along with the headspace increase, and not stepped.

 

[cire]

Ok. I'm not sure why you addressed that to me, though. My point was that there's no magical breakpoint at "half full," and that the decrease in CO2 volumes in the beer is continuous along with the headspace increase, and not stepped.

By way of explanation, from your reply it seemed to me you were probably unfamiliar with the vessel and system used by the OP. Those who are would know what was meant by the OP, nor contemplate a pressure step. Mistakenly, I thought an explanation might have some merit. Please ignore all that follows.

Ale at cellar temperature (56F) with the right amount of priming and a known yeast can keep the pressure near to constant if matched to your rate of consumption. I have seven such vessels with four in current use. A small bottle of CO2 is all I need, but it is only rarely used and if my rate of consumption is less than expected, the pressure increases and the safety valve operates.

As said, King Keg Top Taps require more internal pressure to dispense the beer with equivalent pour from a bottom tap which has the vessel pressure plus that from the static head. As the vessel's upper pressure limit is the same for both types of vessel, the Top Tap version potentially require more gas and their owners are more cautious when their gas reserves are low.