How does kegging work in a brewery?

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How does kegging work in a brewery?

Post by timmse » Sun Sep 21, 2003 8:13 pm

Hi guys

I was wondering the other day how kegging is done in a brewery? The part im interested in is the addition of co2 to the beer going in to the keg. how do they get it into the beer without shaking the keg like the rest of us :)? The beer coming from the FVs should have the same co2 content as our beer before being kegged. Any help will be greatly apreciated, I cant sleep at night :).

Thx in advance


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Kegging 101

Post by Brewer2001 » Sun Sep 21, 2003 10:58 pm


This is my secind attempt I hope I get it all in. I had a good three paragraphs for you.

Well here we go again. Racking is quite different in commercial breweries. They set specific carbonation specs for each of their beers (small breweries may just approximate this). When sealed kegs (Sankey, Hough-Stevens and sometimes Golden Gate) are filled they pre-pressurized with CO2 to between 10-15 psi. This is done to purge the O2 and to minimize gas break-out during racking. The kegs are connected to a conditioning or bright beer tank ether singley or in multiples using a manifold. Some breweries return the vented CO2 back to the tank and some vent it to the atmosphere and spill the foam to a bucket or a drain. In the case of open kegs and casks(Sankey conversions, Hough-Stevens, Gonden Gates, Firkins) they are sometimes purged with CO2 prior to filling. The beer is filled at a faster rate to encourage fobbing and "bung on the foam" to expel any trapped O2.

Cornilius kegs are usually filled from a 1/2 barrel keg and not the tank. This is safer for the beer, less chance of contamination and easier when you need to rack larger volumes of beer.

You do not attempt to shake a 1/2 bbl keg!
Here is why: 1 U.S. gal. = 8.3 lbs.
1 U.S. bbl = 31.0 U.S gal. (258 lbs.)
1/2 bbl keg = 15.5 U.S. gal.
1/2 bbl keg tare = 23-28 lbs.

So a 1/2 bbl keg weighs 8.3*15.5+(23-28)=151.6 to 156.6 U.S. lbs.

Kegs tend to go where they want to if put in motion! I have a lot of first hand experience.

In a commercial brewery the beer is brought to the desired carbonation before it is kegged. If it is bottled the carbonation may be lowered to make it easier to handle. Bung filled kegs were also pressure filled in large breweries.

I hope this helps you sleep. If you want more info see if you can get a copy of the 'Practical Brewer'. It won't help much in your homebrewing but it will give you ideas on "big commercial" brewing.

Good brewing,

Tom F.

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