veers to where the wild things are—as in the [wild] sour beer microbiome— and taming is his quest.
What —you rightfully ask—is a sour beer microbiome and why does it need taming?
According to Bochman, Assistant Professor of Molecular & Cellular Biochemistry and Affiliate Assistant Professor of Biology at Indiana University
, the answer is because sour beers “are made with a bacterial and fungal mix, rather than pure cultures of Saccharomyces yeast as in typical ales and lagers, the suite of different microbes and their relative abundances during the course of souring and fermentation remain a mystery.”
Mysteries don’t make for consistent quality in brewing. And at a time when sour beers are gaining appeal and more breweries are getting into sours production, ’taming’ the wild yeast is a good business plan.
“We aim to map part of the sour beer microbiome and identify the organic acids these microbes produce,” explains Bochman during a telephone conversation.
The call was a followup to an email message: “My lab is embarking on some new sour beer research. We're collaborating with Blue Owl Brewing
in Austin, Texas
to map the sour beer microbiome (probably not what Obama was thinking with the National Microbiome Initiative). Because biological research is expensive, we're going to try to crowdfund the project on Experiment.com
, which is a new type of funding mechanism that is popping up more and more in science these days.”
June 16, I found the Experiment.com site and learned 76% of the required $5,892 has been pledged by 24 funders with 19 days left to gain the full amount. It seems certain to move forward. If you are interested, in joining in, please click here
Bochman’s research is in conjunction with Jeff Young
, director of brewing operations at Blue Owl Brewing in Austin, Texas. Blue Owl founder Jeff Young is dedicated to sours. His bio states: “I have been brewing for over a decade and was previously an analytical chemist at a pharmaceutical company. My passions for art, science, and engineering come together in the brewhouse! I left my previous brewery, Black Star Co-op Pub and Brewery
, to focus solely on sour-mashing and the novel, seemingly endless possibilities of integrating sourness to any beer style.”
Young’s passion lines up with Bochman’s quest. “I’ve been working in research labs for 15 years, using the model organism Saccharomyces cerevisiae to answer a variety of scientific questions,” Bochman writes in his bio. “For the same amount of time, I've been an active homebrewer using the yeast S. cerevisiae to make beer and hard cider.”
Bochman initiated several fermentation-themed projects, which led to starting a business—Wild Pitch Yeast
— to provide yeast and lab services to craft and homebrewers, which now has led to the Blue Owl Brewing project.
The goals for this project, according to Bochman and Young “is to determine the microflora on various malted grains and to sample souring beer at various time points to determine which microbes thrive, grow, and ferment during wort-souring.”
The experiment requires Young at Blue Owl Brewing to collect the samples over the course of 24 hours. According Bochman his lab at Indiana University “will then isolate microbial DNA and prepare next-generation sequencing libraries. The DNAs will be sequenced and the samples compared to one another to: 1) determine the species present and their relative abundances at each time point; and 2) how that microbial community changes with time. The organic acids in the final beer (lactic acid, acetic acid, etc.) will also be identified, as these are the compounds that the tongue recognizes as sour.”
“If we can understand souring at the microbial level, we can tame it, yielding predictable batches of beer time and again,” predicts Bochman. "The affordability of utilizing naturally occurring bacteria found on grain (sour-mashing or sour-wort), if controllable, will yield an easy, accessible way for all brewers to experiment more with sour beers.”
NUVO initially caught up with Matthew Bochman when he worked with Upland’s
Sours brewing team early 2016 to help stabilize the bottle conditioning phase of Upland’s ‘Cauldron
’—an apt name for a brew that’s not quite ‘eye of newt’ witchcraft but nevertheless was acting up in unpredictable ways.
We next caught up with another aspect of Bochman’s foray into wild April 9 at the Bloomington Craft Beer Fest
at Woolery Mill
when we tasted the experimental batches brewed by Steve Llewellyn
. He begged the question: What differences could we detect between a regular [not sour] recipe utilizing the brewery’s commercially purchased yeast and a batch fermented from yeast collected and nurtured from a site around Bloomington?
At Upland’s June 4, Sour Wild Funk Fest Seminar
we learned about Bochman’s role in Upland’s The Spontaneous Project
, barrel-aged ales brewed with locally foraged microflora. Quoting directly:
In The Spontaneous Project, we have barrel aged beer with select naturally occurring local microflora, collected from some of our favorite remote places in Monroe County in the spring of 2015.
Quarry: The results of fermentation with agents collected from the Woolery Mill in Bloomington. This straw colored sour ale has aromas of strawberry lemonade and wild yeast character. Dry, tart, and cider flavors with hints of tropical fruits.
Sky: The results of fermentation with agents collected at The Scenic View Property above Lake Monroe. Barnyard aromas and slight fresh leather around a sour nose. Earthy and fruity flavors, with a dry and tart finish.
Forest: The results of fermentation with agents collected from the Hickory Ridge Tower, the last fire tower in the Hoosier National Forest. Perry aromas with hints of barnyard. Cidery flavors with a crisp lactic tartness.
Creek: This bottle holds the results of fermentation with agents collected along the bank of Bean Blossom Creek. Tropical fruits and wild yeast aromas. Lemon and white wine flavors with dry tart finish.”
The process required collecting and propagating until an adequate yeast culture started growing from each of the four collection sites. Indeed, location creates a totally different taste profile, which we noted during a blind tasting. Based on unscientific conversation following the blind tasting, which brew we liked best and liked least matched up with what we generally like—no surprises there.
These four beers, over a year in the making are also part of the Indiana Humanities INConversation Project, for which Upland is the Indiana craft brewery sponsor. Learn more at: IndianaHumanities.org/Campfires
Bochman is not alone in pursuing the wild side. An Associated Press posting on June 12, 2016 reports that Stephen Fong
, an associate professor of chemical and life-science engineering in the department of Chemical and life sciences at Virginia Commonwealth University
in Richmond, Virginia, “is lending his expertise to the region’s fledgling craft beer industry. In Fong’s lab, the flasks of liquid wort—essentially unfinished beer—grow strains of wild yeast collected from the Jamestown historic site.”
Based on the turnout at Upland’s Sour Wild Funk Fest, a lot of people are happy with a consistently good brew from their favorite brewery and definitely are up to unexpected flavor profiles provided from wild strains of yeast at sites we like to visit.
“Mother Nature created over 150,000 yeast species, but only a handful currently are used by craft and home brewers,” states Bochman. He’s set on “delivering the tastes and smells [we’re] missing” by partnering with brewers bold enough to go where the wild things are.