Carbon dioxide created during the brewing process is fed into separate tanks to help the algae grow. Photo: Supplied
Researchers across the ditch are making good progress in their efforts to reduce emissions created from the brewing process, while also creating benefits for livestock.
For the past seven years, brewers from Australia's Young Henrys have been working with a team from University of Technology Sydney to remove carbon dioxide from the beer brewing process through growing algae which absorbs it.
Dr Peter Ralph, a professor of Marine Biology and executive director of the Climate Change Cluster at the university, describes beer manufacturing as the "perfect yin and yang" of carbon dioxide (CO₂) and oxygen.
"Yeast absorbs oxygen and makes CO₂. Algae absorbs CO₂ and makes oxygen," he explained to Country Life.
"So [in] the process of making the beer, you need to ferment the yeast, and therefore you make CO₂. An organism like algae wants to take up that CO₂."
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The algae is grown in photobioreactors between the vats of brewing beer. The CO₂ created through the brewing process is fed into these reactors.
The oxygen created by the algae isn't added back into the brewing vats, but helps offset the CO₂ generated during the beer making process.
It was an idea appropriately settled upon over a few brews.
"The co-founders of Young Henrys saw an opportunity that they thought there was potential in integrating algae somehow into their process," Ralph said.
"And about the same time we were interested in finding a local brewery that we could test some methods out. And I think we met down at the brewery and we started putting some ideas down on the table, and Young Henrys loved it."
More recently the team have been adding the algae to spent grain from the brewing process, creating pellets that can be fed to livestock to help reduce their methane emissions.
Ralph views it as a creating a "circular economy" system.
Peter Ralph, Professor of Marine Biology at University of Technology Sydney, and executive director of the Climate Change Cluster. Photo: Supplied
"In Australia and New Zealand, we know that our livestock are methane-emitting. Both cattle and sheep emit methane through a natural process."
Research into how to reduce methanogenesis in the gut of cattle and sheep has found a promising solution in the form of bromoform, which comes from a type of seaweed called asparagopsis. The bromoform acts as an inhibitor for methane production.
While Ralph and his team are working with microalgae, they've found similarly promising results through lamb trials. They've also found there's an impact on the health of the animal and the quality of the meats that come from it.
"There's a wide range of benefits that feeding algae to livestock can generate."
The algae is added to spent grain from the brewing process which can be turned into pellets. Photo: Supplied
The team hopes to begin cattle trials in the near future but will need to scale up their algae-growing efforts.
"When you do feeding trials, you have to use an awful lot of algae to even be a small percentage of the feed for lambs. And if we had gone to cattle trials, we would have needed ... more algae to be made. So one of the challenges is growing enough algae to do these trials."
They've recently secured funding to screen other types of algae to see what are the right algae to grow at scale.
"Most algae will grow well in a CO₂-enriched environment, but it's working out which ones grow well in a CO₂-enriched environment and also have that benefit for the feed, reducing methane, making the growth rate faster of the lamb or the cow, and ensuring that we've got a healthy animal."
Learn more:
- You can learn more about the project here.
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