This week we’re talking about optimizing pressure and temperature for a perfect pour
Intro to carbonation
CO2 saturation is an important nuance of many beers. Most beers have an ideal temperature and CO2 level that they should be served at for optimal taste. If the keg set up is even off by as little as 2 PSI of CO2 or beer gas, it can drastically affect the taste and texture of the beer being served. Follow this basic rule – lighter beers generally have more carbonation than hoppy or malty beers.
The volume of CO2 that is absorbed into the beer might vary significantly depending on the temperature of the beer or keg, which further complicates issues. This is due to the fact that when temperature rises, less CO2 or beer gas is absorbed into the beer. In a similar vein, if the temperature drops, more CO2 or beer gas may be absorbed into the beer. As a result, when the keg’s temperature rises or falls, difficulties result.
The common 5 lb CO2 tank should last 14-22 sixtel, corny, or homebrew kegs depending on the beer your serving.
Pressure
Most American brewers recommend a CO2 pressure between 12 and 14 PSI, and we propose putting the regulator at 12 PSI under normal conditions. Most types of beer can be served at this pressure, with the exception of stouts, which can be served at 35 to 38 PSI. It may also be necessary to compensate for other factors, such high altitude, the length of the beer line, temperature fluctuations, or unique beer varieties.
Unreliable pressure can lead to under- or over-carbonation, which can result in flat beer or excessively foamy beer.
Temperature
The ideal range for chilled beer storage and serving is between 36° and 40° Fahrenheit, or high 30s to mid 40s. (Remember that beer freezes at a temperature of 27°, with light beers freezing at a temperature of 31°.) The ideal pouring temperature for the great majority of beers is 38°F. The degree of carbonation that was produced during the brewing process will remain in beer that is stored at this range.
You might want to change the temperature control to a colder level throughout the summer.
When the keg temperature deviates by two degrees Fahrenheit from the desired temperature, you can counteract this by raising the PSI of the beer gas by one PSI.This is due to the beer absorbing more CO2 gas internally, which lowers the pressure inside the keg and in the line. Similar to this, you can lower the pressure by one PSI for every two degrees over or below optimal temperature that the keg has reached.
Dialing it all in
A well functioning system will fill a pint glass in about eight seconds and a gallon of beer in about a minute. Recall that the optimal pressure for most beer styles is 12-14 PSI. Keep your system around 38°F, and remember to adjust you pressure by 1 PSI for every 2 degree change in temperature. If your beer has a harsh, acidic flavor and fragrance, tiny bubbles that resemble seltzer water, and a gritty texture, it may be over-carbonated. If it tastes watery, has bubbles that are larger than usual, or is motionless, it may be under-carbonated. Cheers to a perfectly poured pint!
Next time on Kegerator Secrets we’ll talk about the optimal settings for wine, cocktails, and non-alcoholic beverages. Stay Tuned!
