AUSTIN - The fresh, doughy aroma around the conical fermentation tanks at Austin Beerworks is a sign that trillions of yeast cells are turning the sugary, hoppy liquid inside into beer. But there’s another byproduct: carbon dioxide. Fermentation releases CO2 as the yeast breaks down sugar to create alcohol. At most wineries and breweries, it is released into the atmosphere. But a growing number of craft breweries are starting to collect that gas, not only reducing CO2 emissions - even if by tiny amounts - but also reusing it to give beer its characteristic white foam. Until recently, Clinton Mack, Austin Beerworks’s cellar manager, had to truck in carbon dioxide in tanks 10,000 pounds at a time. But now, he’s using techniques developed by NASA to capture the naturally produced CO2 and dissolve the molecules into his brews. “The technology isn’t simple,” Mack said, “but it’s, like, why aren’t we using it?” The machine that enables Mack to capture CO2 from Austin Beerworks’ tanks is the size of a large, double-door refrigerator. Nicknamed CiCi - short for “carbon capture” - it takes in CO2 that flows from the fermenters through pipes that snake around the brewery, filters it to more than 99 percent purity, and condenses it into liquid. The machine then stores the resulting condensed gas for use elsewhere, including to carbonate beer. Mack said installing the technology, made by Austin-based Earthly Labs, was a no-brainer. The average batch releases about one-third of a pound of CO2 per gallon of beer, which adds up to about 210,800 pounds a year from a brewery like Austin Beerworks. That’s about the same amount of CO2 that 21 gas-powered cars release in an average year. But while preventing fermentation emissions from being released into the air is a plus, Mack said, it’s also a cost-saving measure for the brewery. CO2 itself is a valuable ingredient in beer production. The fizzy white bubbles on your favorite... |