Kegsack: Lose CO2 With BIAK

This article originally appeared in the July/August 2024 issue of Zymurgy Magazine

By Pierre Margraff and Andy Tipler

This is the third and final article of our Zymurgy series on how homebrewers can minimize the necessity of using tanked carbon dioxide (CO₂). The first article investigated how the use of CO₂ more efficiently with traditional practices, and the second considered the generation and use of home-produced CO₂.

Our third article examines the use of pressurized CO₂ for the dispensing of kegged beer. Draught beer usually requires some form of driving force, normally gravity or gas pressure, to push the beer out from the keg, through some tubing and a faucet, and into the serving glass. Using gravity is still an option for some beers, notably English cask real ales. For beers requiring higher carbonation levels, gas pressure is the main option. Because this gas is in contact with the beer and needs to maintain the beer’s condition, it’s usually CO₂, although nitrogen (N₂) is used for some beer, particularly stouts. So, serving beer from pressurized kegs normally requires a source of pressurized CO₂. Because the beer is often dispensed over some time, the CO₂ supply must be readily available when needed, so tanked CO2 is usually the best option.

How much CO2 do we need to fully dispense a keg of beer?… What options do we have to reduce or even eliminate this moderate consumption of tanked gas?

Access the full article in the July/August 2024 Zymurgy Magazine.

This article includes the following:

• Calculating the amount of CO₂ needed to dispense a keg of beer
• The Bag In A Keg (BIAK) system concept
• Commercial BIAK systems
• DIT BIAK system
• In-depth look at the components of a BIAK system
• Discussion, conclusions, and final thoughts