But, beyond that, yeast has the potential to transform the world of beer, giving it more complex flavor profiles and unique regional differences. So say Rob Green and Mara Young, the husband and wife behind San Antonio-based Community Cultures Community Yeast Lab.
The couple teamed up in 2016, drawing on Green’s work as a microbiologist, Young’s managerial and entrepreneurial experience and their shared love of nature. They officially launched their business the following year selling 10 varieties of saccharomyces, a type of fungi that can be used to brewing beer.
“We realized that there weren’t really any true American yeast strains, even though the American craft beer scene has been going on for a couple of hundred years,” Young said. “But Rob said he wanted to find them.”
Their company, previously known as Texas Community Cultures, has since expanded using yeast samples found during hiking trips and from people they dub “community scientists” who volunteer to help collect yeast strains.
The couple also operates a 1,100-square-foot lab, from which they provide yeast testing and cloning. They even offer manufacturing services for craft breweries and distilleries throughout the U.S.
Yeast naturally forms a variety of flavor compounds during the fermentation and maturation processes — evoking everything from green apple and sweet fruits to butterscotch, spicy cloves and medicinal notes — that, along with hops and water varieties, determine a beer’s taste profile.
“Yeast drives up to 70% of a beer’s flavor profile,” Young said. “There are many subspecies of saccharomyces, but only a fraction has been discovered to date. We’re hoping to find those new ones.”
Today, Community Cultures works with more than half a dozen San Antonio breweries, including Alamo Beer Co., Künstler Brewing, Issla Street Brewing, Mad Pecker Brewing Co., Basement Brewers and Cactus Land.
Its fingerprints are on several high-profile local beers such as the recent collaborative effort to recreate San Antonio’s first commercially brewed beer, named Degan’s Famous Beer, which first brewed in 1885. Community Cultures worked with local brewing expert Jeremy Banas to recreate the beer again, introducing the brew at Alamo Beer Co. earlier this year.
Degan’s is expected to roll out on an even wider scale, although the collaborators haven’t yet finalized how it will be manufactured and distributed.
Commercial brewing yeast typically uses neutral strains designed in a brewery, with multiple copies of genes that are resilient and hardy. Most mass-produced beers are produced with neutral strains, which results in an easily drinkable but often flavorless brew.
“We’re still in the drinkability era, where people say, ‘I want to taste the lager with no flavor in it,’ basically,” Green said.
Where Community Cultures hopes to make a difference is by getting craft brewers shift to using wild and native yeasts.
Wild yeast strains produce little to no alcohol, while native yeast — a type of saccharomyces — primarily produces alcohol. In contrast to commercial yeast, neither type is engineered or perfected over generations, but they tend to capture the terroir, or flavorful essence of a particular place, as defined by its natural surroundings.
In recent years, breweries have used hops to impart extra flavor to the grains that account for a beer’s body. Community Cultures champions the idea that the same can be done with yeast.
“Five hundred years gone is the idea that the yeast would actually do all the flavor,” Young said. “We’re talking monks with barrels here. Whatever grain happened to fall into the mash resulted in the flavor you got.”
Though Community Cultures works with many local breweries to improve and perfect existing beer styles, the couple is always ready for newcomers to rethink existing beer styles by introducing new yeast strains.
“Our hope is that with our native strains, people will break outside the existing beer mold a little bit,” Young said.
With the potential to discover new subspecies of saccharomyces, brewers still have the potential to create something completely new.
“New strains don’t have a set style. It’s not a Belgian, it’s not a Hefeweizen and it’s not a French saison,” Young said. “So, what are you going to do with it?”
When the couple isn’t working at the lab, they’re traveling to meet with professional brewers and hobbyists, and always looking for new opportunities. In the coming months, beer lovers can look forward to seeing more brews incorporating the company’s yeast.
For example, Community Cultures recently used a strain of yeast found at Big Bend National Park to create a collaborative beer with Dorćol Distilling + Brewing Co. to help commemorate the park’s 75th anniversary. It’s scheduled to drop this month.
For the couple, the possibilities are endless.
“There’s potential to take all that creativity and build it around a wonderful thing’s that been never been discovered before,” Young said.
Editor's Note: A previous version of the article misstated Community Cultures' role in recreating Degan's Famous Beer; it has since been corrected.
So many restaurants, so little time. Find out the latest San Antonio dining news with our Flavor Friday Newsletter.