We never advocate setting the CO2 pressure at the warmest or coldest point of a system for ales and lagers. It must be set at the temperature of the beer at the keg. If a direct draw system or short remote is incapable of maintaining this temperature from the keg to the faucet, either correct the situation or use an on-site gas blender.
The Micro Matic workshops recommend 60% CO2/ 40% N for ales and lagers between the 2.2 and higher range. This will gain perfect equilibrium for the lower end of the spectrum and suffice for the higher volume. Take care of the more expensive slower turning products and still maintain the higher carbonated, faster turning domestic products. Can this be dialed in perfectly for every condition that exists at retail? Absolutely. Not practical.
It is a challenge to revert the gains of gas companies all across the country who are outselling just about everyone in the beer industry with their 25%CO2 / 75%N premixed beer gas in a cylinder. A product that is by far causing more quality issues with draught today less line cleaning issues.
The on-site 60% CO2 / 40% N mix is a ratio that will be much more successful in preserving gas content. Consumers will not be able to detect the changes in carbonation level if the gas content changes slightly for the higher carbonated products. At least not to the point where they deem it undesirable. It just is not practical to have multiple ratios (gas blenders) for the different gas contents between the ales and lagers.
We are doing what we can as an organization to transfer this knowledge to the industry through our workshops at our training facilities, beer wholesalers and other industry entities. Hopefully enough momentum will be gained to convince the retailers who are using the premixed gas for ales and lagers to realize that the gas companies are not looking out for their best interest. They by far are the largest threat to the quality of draught beer since air compressors (less those gas companies who are providing the nitrogen generators).
Scott Zuhse, Instructor
Micro Matic Dispense Institute