When dispensing keg draft beer, the goal is to maintain the beers’ carbonation (CO2 level measured in volumes [v/v])  prescribed by the brewer. Any change at thekeg and / or throughout the system will impact the taste, pouring characteristics of the beer and final presentation in the glass.

If CO2 is applied source to the keg, recommended pressure will be between 12-14 lbs. to maintain typical ale and lager type beers’ carbonation.  A beer carbonated with 2.6 v/v and its temperature in the keg is 38°F requires a regulator setting of 14 lbs. The more carbonation, the higher the pressure. Conversely, less carbonated beers require lower pressure. If pressure is too low, the CO2 (carbonation) dissolved in the beer will “break out” resulting is foam thus dispensing issues. Continually dispensing foam will reduce carbonation of the beer in the keg – flat beer.

As well, temperature directly impacts regulator setting. Colder, less pressure. Higher pressure with warmer beer. If you are unsure what the correct CO2 pressure should be, refer to the flashlight test. Ideal test on a fresh, acclimated keg draft beer.

CO2 pressure source against beer in kegs may not be the best solution with systems that have uncontrollable temperature fluctuations or dispensing is at a remote location. Most certainly CO2 has limitations as to temperature issues and with the lower pressure settings associated with it, is incapable of dispensing beer distances.

A gas blend of some CO2 to maintain carbonation with a non-reactive gas such as nitrogen for additional push is perfect when just CO2  falters. A correct ratio of these gasses via a gas blender allows for higher applied pressure to the beer keg compensating for slight temperature fluctuations and for dispensing remotely. Often, based on system design, a ratio of 70% CO2 / 30% nitrogen is ideal when pressures to keg are between 20-25 lbs. and beer is 38° F. Contact Micro Matic if unsure of correct application and ratios for gas blends.