Franconian Beer Message Board

Das heilige Bauchfass
Posted by Mosquit on 2017-04-20 03:06:42


Few words to it. 

Everything is a matter of the KEG "pushing" pressure and where the KEG is located. 
If you have a KEG in minus 2nd floor (underground), you have to push it with a lot of pressure to bring it to the taproom. Regardless of whether it is a CO2 or "biogon" (mixture of nitrogen and CO2), it must be pushed with a higher pressure. As far as I remember from physics lessons at school, this should't actually affect the flow speed at the tap when it is being poured into the glass. However, I think that this pressure is simply being often set higher than needed (by bartenders / bar owners), which then makes beer to be poured with a bit higher pressure than from gravity... 

Also, this speed with gravity barrel is actually changing as barrel gets empty - not sure if you have ever noticed that, but first X beers is usually much LESS gassy, since tapping them takes more time (two-times, three-times) and CO2 gets out. 

That all applies when assuming that KEG is empty in a couple of hours. If you leave it under CO2 overnight, especially in cold environment, it absorbs some CO2 and gets "gassy"; that is a different story. And this (I guess) is really happening; I don't believe that in small-villages (like Merkendorf) they could finish KEG of the beer every day, when they have 7-8 different beers on tap (both Wagner and Hummel). 

 
 
Followups:
                     Das heilige Bauchfass by Barry on  2017-04-20 03:41:28