Every week, Darwin Brewing Company in Bradenton needs to get rid of thousands of pounds of soggy barley.
Known as spent grain, the cracked kernels are a byproduct of making beer, each a little bigger than a grain of rice. Usually, farmers haul off totes of the grain for their livestock to eat, said Blue Hellenga, Darwin’s head brewer. But more recently, some of it has gone to a new destination at the nearby Mote Marine Lab.
Researchers there are trying to find ways to thwart Red Tide, a scourge for Florida’s Gulf Coast. They believe the used grains could hold an answer in molecules that stunt algal blooms. Red Tide kills fish in droves and forces sunbathers off the beach. Besides the putrid smell, it causes breathing problems.
In early tests, the kind of molecules that exist in spent grain have killed small amounts of the organism in Red Tide within a few hours, said Vince Lovko, a staff scientist at Mote.
“It was pretty surprising to see such an immediate effect,” he said.
Scientists working with the beer byproduct caution that they are still early in their research. It’s not a miracle cure, and Floridians shouldn’t plop barley into their bays any time soon. But the limited results so far show promise.
Molecules called flavonoids are essentially “suppressing growth” of Karenia brevis — the microorganism behind Red Tide, said researcher Allen Place, a professor in the University of Maryland’s Institute for Marine and Environmental Technology. The flavonoids might undercut photosynthesis, which is how Red Tide gets its energy to live.
A key next question is what happens to the toxins in Red Tide when the cells die.
“Do we just have a big blast of toxins for the short term?” Lovko asked. That would only exacerbate a fish kill, and necessitate a second treatment option to eliminate toxins.
If it all works, whole grains would not be dumped straight into the water but would be used to extract flavonoids and possibly some acids that would then get mixed with Red Tide. Lovko said the barley on its own contains compounds and nutrients that could hurt the environment or further fuel a bloom.
The necessary molecules are marketed in purified form, which the researchers have used in their studies, but they hope beer byproducts offer a stable, cheap source of the material they need.
“If you look at all the microbreweries in the U.S., the amount of spent grain that is made is ridiculously large,” Place said. Hellenga estimated that Darwin produces about 5,500 pounds of it in a typical week.
“No matter what happens to the economy, we’re always going to be drinking beer,” Lovko said.
Matt Cornelius, sales director for Darwin, considers the pairing mutually beneficial. Brewers look for any way they can to dump spent grain. Plus, he said, “we rely on the conditions of those beaches being pristine.”
Florida has not suffered a big Red Tide so far this year, according to weekly monitoring from the state Fish and Wildlife Conservation Commission. In 2018, blooms darkened the water, killing many thousands of fish — which washed ashore on beaches — and hurting the coastal economy.
Mote is working with several research partners and about a million dollars in funding to better understand Red Tide.
The grain study originated with the University of Maryland, where Place’s lab looked at an algal bloom plaguing the lake of a local Girl Scout camp. Scientists threw in bales of barley straw, which rotted and released molecules. Such an approach takes time, requiring the bales to be put out even before a bloom begins, said graduate research assistant Taylor Armstrong. So she started to brainstorm, and when she thought about barley, she thought about beer.
Spent grains are “ready to decompose,” she said. “You don’t have to wait months.”
The compounds, according to Armstrong, have also shown potential to knock down parts of equally notorious blue-green algae, which involve bacteria and typically sicken people and animals around freshwater.
While she said the work will at best offer short-term relief, the ultimate aim should be limiting nutrients that allow harmful algal blooms to thrive. That means curbing nitrogen runoff into waterways from industrial pollution and farms.
The pandemic, Armstrong said, offers an easy parallel. “Like with COVID, it’s treating the symptoms and not the problem. Your goal is for you not to get COVID in the first place, or not to get a bloom in the first place.”