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Recapturing CO2: It’s a Gas

Brewers are dumping their blow-off buckets and reusing precious carbon dioxide rather than releasing it into the atmosphere. The benefits include cost savings, reducing greenhouse emissions—and, some say, better beer.

John M. Verive Apr 8, 2022 - 15 min read

Recapturing CO2: It’s a Gas Primary Image

Gregg Spickler, director of brewing operations at Alamo Brewing in San Antonio, connects the foam trap between a fermentor and the Earthly Labs CO2 recapture system. Photo: Courtesy Earthly Labs

Do you know where the bubbles in your beer come from? It may not be exactly where you think.

Yeast, of course, produces the carbon dioxide (CO2) along with ethanol and all those tasty esters and phenols. However, only a small percentage of craft beer contains carbon dioxide produced during its own fermentation. Most of that gas escapes into the atmosphere, bubbling away in blow-off buckets and adding to greenhouse-gas emissions. Most canned, bottled, and kegged beer is force-carbonated and packaged with bulk CO2, which local suppliers deliver to the brewery at regular intervals.

Busy breweries tend to operate like machines, and using CO2 from bulk suppliers is one of those cogs in the machine that just works. Few give much thought to all that gas produced by the yeast. It just bubbles out into the atmosphere because it’s easy and relatively cheap to purchase CO2 from a third party. After all, gas is gas. Right?

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