Push Pressure

[uscbrewer]

Quick question concerning push pressure. I've noticed in a couple of posts that the breweries recommend upping the pressure two psi to compensate for the opening of faucets, etc. From what I've read, this will eventually cause overabsorption, but that it won't affect anything in the short term.

I usually finish my kegs in about a month. If I am taking that long to finish them, should I still add the push pressure, or should I go with the equalibrium pressure? Right now I have a 1/4 keg of Bud Light at 38F and I split the difference on the psi and have it at 13psi. Not sure if should reduce it to 12 or kick it up to 14. I am at sea level.

Thanks!

[Draught Prophet]

Good question. Push pressure is there to help ensure an even, full column of beer to pour out of the faucet. The problem with under-carbonation (lower applied pressure) is that your flow speed will slow down which may result in foaming. Your column of beer will not be clear, just slightly foamy. Same thing with higher applied pressure. I would leave it at 14 unless you start to see it over carbonate, then turn it down to 12 or 13.

You should be fine at a month, I know many people say that you should consume a keg within 3 days of tapping, but that’s old school talk. With technology today to provide constant temps and pressure and pouring through better quality lines and using better cleaners, I firmly believe you can go 6-8 weeks before quality slips. I can tell you that the shelf life that brewers give their kegs is also on the low side so that people will try to uphold the brand quality. They can’t say 120 days on a keg incase you hit 110 and it’s bad, so they underestimate and say 60 (for example). Just ensure it’s always cold and still and always has been.

Anyhow, most people can’t tell a change in co2 volume within a half a volume or so, so you won’t affect it much by moving it from 14-12 or vice versa. Your main concern should be flowspeed.