While the science behind chemical blending is complex, its application is far simpler to understand. First, you need to understand that different types of gases help to enhance the overall flavor characteristics associated with certain craft beers. CO2 (Carbon Dioxide) is used to give beer and sodas that nice characteristic fizz when you drink them. On the other end of the spectrum, nitrogen can be used to give beers a fuller texture with a nice “mouthy” feel. In fact, nitrogen is even considered as a “must have” when it comes to certain craft beers since it is responsible for that foamy characteristic that helps to truly make beer look enticing.
Combining the two gases is what chemical blending is all about and is the secret behind great tasting craft beer. However, the process behind combining the two gasses involves more science than crafting skill. First off, adding C02 to beer can be done naturally using sugars and yeast or it can be done artificially utilizing carbon tabs or high pressure application.
When it comes to CO2 and nitrogen being added together, this involves the use of a chemical blender that uses the applied gas pressure of both to saturate the beer. This mix is normally a combination of 70 percent nitrogen and 30 percent carbon dioxide; however, this proportioning can be shifted depending on the type of flavor profile that the brewer is after. The gases can only be mixed under high pressure since just leaving it out in the open and releasing nitrogen and carbon dioxide via tanks simply does not work, pressure is required to do the job.
That is why craft beer is normally placed into sealed kegs, cooled down via refrigeration and then simultaneously pumped with nitrogen and oxygen until the beer absorbs both gases. Do note that this absorption is not permanent and the gases will escape the beer over time as soon as it is released from the pressure. This can be seen in the case of the foamy bubbles that appear on top of a beer mug as well as the taste of beer after it has been left out for 20 to 40 minutes in the open air. The “flatness” of the beer is a direct result of the gases having completely escaped which shows that the nitrogen/CO2 blend is essential in creating excellent beer.
All in all, what this article shows is that making excellent craft beer is a combination of a brewer’s skill as well as the science of chemical blending. You need to get a good combination of the two if you want to establish a great brand.