Robert 'Rusty' Bryant tends to his Asheville Brew Bites booth alongside wife Mary during the Cool Craft Market at HandMade in America on Dec. 15. The Bryants' small company sells brownies made from brewer's yeast, the byproduct of beer-making. / Colby Rabon / Citizen-Times photo
Biochemist Rusty Bryant tried 42 versions of his brownie made from brewer's yeast before he hit on the right recipe. He makes the brownies at Blue Ridge Food Ventures. / Erin Brethauer / email@example.com
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Asheville is increasingly known for its brewery scene, with bigger national beer-makers becoming part of the local economy.
Such big breweries produce plenty of waste and, at least locally, responsible disposal is a part of the brewing mission statement.
According to one local scientist, one possible avenue is to eat that waste.
Robert “Rusty” Bryant, a former biochemist with Schering-Plough Research Institute, is the co-owner with his wife of Asheville Brew Bites, a small company making brownies from spent brewer’s yeast, a byproduct of the brewing process. Bryant thinks his beer treats could make a big impact on both health and the recycling of the beer industry’s leftovers.
From beer to bites
Bryant first came to Asheville in 2010 to help his son, John Bryant, renovate the Hatchery Building in the River Arts District. Bryant knew nothing about the beer industry then, “other than opening a bottle of beer.”
Then, the future site of New Belgium Brewing was just a collection of lots in a flood zone nearby his son’s property. New Belgium, the third largest microbrewery in the country, is slated to begin primary construction on its new $150 million Asheville location in May. Sierra Nevada, the second largest brewery in the country, is test-brewing at its new East Coast facility in Mills River.
While Asheville’s Highland Brewing Co., which opened in 1994, creates 200 tons of spent yeast per year, Sierra Nevada and New Belgium breweries will each add 2,000 tons or more annually, according to Bryant.
For now, Bryant harvests yeast from Highland and mixes it with other ingredients at Blue Ridge Food Ventures to make a gooey brownie. He then sells his products at farmers markets and craft fairs.
Erica Nelson, the quality control specialist at Highland, says brewer’s yeast disposal is an issue with no current simple solution.
“We can’t just dump the yeast down the drain,” she said. “The city waste water treatment facility can’t handle that much of a biological oxygen demand.”
But unlike spent brewer’s grain, which cows readily snap up, yeast doesn’t do a bovine body good. “It’s 80 percent alive and creates gas in cows,” Bryant explained.
And an environmentally friendly brewery trying to dispose of its byproducts isn’t interested in having cows rip a hole in the ozone layer with methane emissions as a result.
Still, a farmer also collects some of Highland’s yeast, and portions it out in small, measured batches to his herd. “It’s a delicate balance,” said Nelson.
“I think he probably would prefer to not have to deal with it. It’s an extra load or more per week to get that out to the farm and having to dole it out, and sometimes even giving a supplement to the cattle, I think there’s a potential for better options.”
Tastes great, less filling
With Bryant’s work representing a mere drop in the bucket of brewery byproduct disposal, why bother? Brew Bites, said Bryant, are meant to demonstrate that a waste product from a burgeoning industry can be repurposed into something better than landfill or compost fodder.
Brewer’s yeast is high in protein and antioxidants, said Bryant. Even if cows can’t stomach it, humans seem to respond well.
The NYU Langone Medical Center says the yeast introduces beneficial bacteria to the gut. Saccharomyces boulardii, a close cousin to brewer’s yeast, has been used as treatment for irritable bowel syndrome and lactose intolerance. Brewer’s yeast has also been used as a protein supplement and is promoted as an energy and immunity enhancer.
With all of those healthy qualities, why isn’t brewer’s yeast everywhere? Because, apparently, it tastes terrible.
The British experimented with spent brewer’s yeast, developing the spread known as Marmite. The product was included with soldiers’ rations in World War I and used to fight malnutrition in some third-world countries.
But the pungent flavor of the yeast is unmistakable, and the company’s marketing slogan is “love it or hate it.”
Bryant’s grandchildren fall into the latter camp. According to the Asheville Brew Bites website, “while such spreads are popular in England and Australia, the aghast taste responses of his grandchildren suggested he take another tack with Asheville yeast.”
Bryant put his background as a flavor chemist to use in producing a palatable model — but not before he created and rejected 42 versions.
Bryant doesn’t think he’ll dispose of the world’s brewer’s yeast through brownies, but he does think his technique for taming the bitter taste of spent brewer’s yeast could make products more popular than Marmite.
“We wanted to demonstrate that you could do something with the taste,” Bryant said. “And the other (objective) was to show that the yeast is good.”
While Bryant doesn’t know if brewer’s yeast will replace green tea in health-conscious circles, “I will tell you that I’ve sent samples off to Serbia to a group that has interesting ways to measure antioxidant properties,” he said. “And they recently did studies to say that hop acids have some of the strongest antioxidant potential of any other natural product.”
Bryant also thinks that brewer’s yeast could help make our food supply safer.
He’s awaiting the results of a sample of local yeast he’s shipped to the Department of Agriculture to find out if it will suppress the growth of the salmonella in poultry. He believes that, by adding the yeast to the drinking water of chickens, he might be able to eliminate the bacteria, which sickens at least 40,000 people a year in the U.S.
“These yeasts just soak up so much of this stuff,” Bryant said. “It’s quite amazing.”
Recent studies by Bryant and his colleague, professor Seth Cohen at Appalachian State, have shown that yeast from craft brewing has high levels of hop compounds, which have antibiotic properties.
A large portion of the brewer’s yeast industry uses spent yeast from MillerCoors, Anheuser-Busch and other large multinational breweries. Roughly half of that dried yeast goes to making yeast extract for cooking, with the other half going to protein supplements for pets and livestock.
And Asheville might have a leg up over all of those megacompanies.
“Highland yeast had much higher levels of hop acids than that from multinationals,” Bryant said. “We are looking into the health significance of that observation, and our manuscript is about ready to be submitted.”
As far as whether the hops will revolutionize science or dinner, Bryant doesn’t really know.
“I’ve been in science 50 years, and we have a lot of bright ideas,” he said.
As vice president of discovery and research at Redpoint Bio Corp, Bryant and his associates thought they could block bitter taste receptors on the human tongue through bioengineering.
“It didn’t work,” he said. “We spent $50 million, and we couldn’t get a bitter blocker and everything looked right. Mother Nature has a lot of secrets.”
The business of brewing
The North Carolina Biotechnology Center sponsored a “Science in the Mountains” event in April at Appalachian State University, where Bryant presented some of his findings.
The Center works to stimulate the local economy through funding scientific research and has been actively involved with the burgeoning brewing industry.
The center this year awarded a $75,000 research grant to BioNetwork at Asheville-Buncombe Technical Community College to establish the Western North Carolina Craft-Beverage Quality Control Initiative to help support quality control programs in the local brewing industry.
Bryant has received no such grants, but the center is “very interested” in his work, said Dale Carroll, executive director of the Biotech Center.
“One of the reasons we would even be interested in this at the North Carolina Biotechnology Center is that we place a big value on commercializing technology and innovation,” Carroll said. “And as Rusty continues to make progress, a real strength that comes out of this is that spent yeast can replace artificial additives in food products — and that’s a good thing.”
What local breweries do is a perfect example of biotechnology as a real economic driver, from the growing of hops to the production of food from the byproducts of brewing, said Carroll. And he thinks that Bryant’s ideas for spent yeast represent a missing piece.
“(He’s) finding innovative ways to make use of a byproduct from brewing that would not only help replace artificial additives in food products but also increase the options that the agribusiness community has in Western North Carolina for feeding cattle — there’s just a lot of upsides that could come from Rusty’s work.”