The pub, restaurant, bar or even home cellar can seem complicated at the best of times. Getting the gas right for your beverages should be simple. At first glance, it seems straightforward: CO2 for the carbonated drinks, and the slightly more mysterious CO2/Nitrogen mix for beer. Of course, there are thousands of different beers, and one beer gas does not fit all. So whether you’re a rookie bartender left to fend for yourself on a busy weekend, or a home brewer contemplating a new gas set up, it’s vital to get a handle on how mixed gasses work.
Beer gases usually come in the following blends of Carbon Dioxide and Nitrogen (this is also the order they appear in the ratio): 60/40, 30/70 and 50/50. This is because the two gases interact with liquid in slightly different ways.
This gives the familiar ‘carbonated’ sensation. This characteristic fizz is perfect when CO2 is pumped pure for soft drinks, and gives the refreshing sparkle to your favourite lager.
This produces a smooth creaminess; the foaming head. It also ‘pushes’ the beer without making it too fizzy, which is to say it enables the beer to be more highly pressurised, ideal if your cellar is any distance from your tap.
Beer Gas Troubleshooting
So, if your lager gas has run dry you should be looking to replace that empty cylinder with 60/40 gas, or even pure CO2. When smooths, ales or stouts go flat, make sure you hook up a 30/70, and if your cider loses its fizz, then the gas to go for is 50/50 (or 60/40 if that’s unavailable).
If you start to have trouble with your draught beverages, it’s always best practice to check the connections and how full the barrel is. Tightening the keg coupler (or putting on a full barrel) is sometimes the quick, obvious fix. On the other hand, if you find your lager is carbonated but barely or your stout is a mess of froth, check exactly what kind of gas you have connected. And if your smooth pours a continuous stream of foam… someone’s switched the nozzles on your taps.
Thirsty for More?
This is just the top line, but for more information, be sure to take a look at these more detailed guides: