Nitro for taproom

[jph2275]

Hello!



I own a brewpub about an hour from Austin, TX and we have decided to add a nitro tap to our current lineup. A customer of ours lent me his stand alone single tap kegerator and we converted it over with a nitro tap, regulator, and 75/25 mix of nitrogen and c02. I was really happy last week about it. I’m less happy this week since it just pours straight foam.



I keep reading about carbonating to 1.2 to 1.5 volumes of c02 and then packaging and pushing w/ 30 psi of nitro c02 mix. This is all great on paper but doesn’t make sense to me in practical application. This seems like an extraordinarily low amount of c02 and one that I don’t frankly know how to achieve?



My stab at it is as follows. I brewed up a stout that had a standard happy fermentation then spunded once things appeared near terminal. PSI read ~4 on gauge after several days. I relieved some head pressure and it stabilized after a few more days around ~2 psi. I crashed then packaged into 1/2 BBL kegs. The kegs sat for about a week at 30psi on beer gas and today I decided to nut up and try to pour it. Foam city. Now at 2 psi respectively at 38° this would land me 1.6 volumes (really close to target). I’m not sure how to get my volumes much lower to the desirable 1.2 area?



It almost seems that I won’t want to add any extra c02 and package the beer nearly flat?



Also beer line length comes to mind. It is 5’ now. Should it be 10’+ or is there some formula I should be aware of?



I am currently bleeding what little c02 is in the kegs off and will try again in a day or two. Does anyone have any advice or any SOP’s they’d care to share?



Thanks in advance!



Patrick

 

[day_trippr]

You are right about the challenge to carbonate a beer to such low volumes. Coming out of fermentation it's likely already sitting at .6-.8 volumes. That is why I carbonate my imperial stout using straight CO2 at "brewery temperature", which is roughly the ~65°F our walk-out basement runs at outside of the hottest and coldest points of the seasons. At that temperature 4 psi will eventually and fairly predictably equalize at 1.2 volumes - and the process doesn't tie up any chamber space

I have a Micromatic stout faucet (truly a massive war club of a thing compared to my Perls) and run 70/30 beer gas at 35 psi through 6 feet of 8mm ID EVAbarrier beer line (keg temperature centered at 35°F +/- 1 degree). Imo, given my previous keezer used 6 feet of 3/16" ID Bevlex 200 for the same faucet, I don't think the line length matters much - except if it's too long. It takes some force to drive the beer through the restrictor plate inside the faucet and at some point too much line will make for a wimpy pour.

Once on tap a full keg lasts for a couple months at least but there's no carbonation creep with that temperature/pressure combination. I've had this beer on tap continuously for well over a decade (I long ago became dependent on a short pour of its 10~11% abv as a nitecap grenade )...

Cheers!

 

[jddevinn]

Pull the tap apart and make sure the restrictor plate is set propertly.