Modern science brews an ancient beer
This article was written as part of a graduate science writing course at the University of Colorado Boulder. Reporting contributed by classmate Nick Mott.
A tour of the Avery Brewing Company in Boulder, Colorado reveals industrial-scale steel fermentation tanks, a laboratory capable of genetic testing and even a hop cannon to add hops without exposing the beer to oxygen.
Yet, the brewery’s latest project is decidedly low tech: making beer as it might have been brewed thousands of years ago in ancient Greece, Egypt and Peru. Using ingredients available to ancient peoples and brewing techniques drawn from archaeological evidence and historical texts, Avery’s brewers hope to offer a new taste from the ancient world.
Travis Rupp
"It's really a combination of my two passions: Being a teacher of ancient history and archaeology and culture, and combining it with being a brewer,” said Travis Rupp, who is leading the project at Avery. "I'm looking at it from the commoner's perspective. What was being cultivated? What's available? What does the archaeological record tell us in terms of their milling processes? And then we’re recreating beers based on that."
Rupp is the research and development manager at Avery and also an adjunct instructor at the University of Colorado Boulder, specializing in Egyptian, Greek, Roman and Near Eastern archaeology. His interest in ancient beer was sparked when his manager at Avery asked him to teach the history of beer in staff meetings. Now, Rupp is drawing on his academic experience as a Classics instructor and archaeologist to bring ancient beers back to life.
He isn’t the first scholar of antiquity to wonder what an ancient beer may have tasted like. Patrick McGovern, a professor of archaeology at Penn State, has analyzed the chemical residue left on the inside of ancient beer vessels. Using his lists of possible ingredients, brewers at Dogfish Head brewery in Maryland have reimagined the ancient beers.
For his ancient brews, Rupp isn’t relying so closely on chemical forensics. Instead, he’s consulting ancient texts, studying archaeological sites where beer was once brewed, and considering the ingredients ancient brewers would have had on hand. As a brewer, he believes how you brew the beer can be as important as the ingredients. His first ancient beer, called Nestor’s Cup, is inspired by the brewing techniques and ingredients of Bronze Age Greece. Two of its key ingredients: wheat made from ground pine cones and acorns.
So what does such a beer taste like? To start, Rupp thinks most ancient beers contained less alcohol than today’s beers–probably only one to three percent alcohol by volume. They also wouldn’t have contained any hops, which weren’t widely used in brewing until the late Middle Ages. So ancient beers were probably much sweeter than today’s. Finally, the lack of hops, pasteurization and refrigeration meant beer would continue to ferment and change flavor with time, likely souring the longer it sat.
While Nestor’s Cup isn’t a sour beer, it has a unique flavor. When Avery first put the ancient Greek beer on tap, one of Rupp’s colleagues described its flavor as “like nothing else that's on this tap wall.” Avery’s patrons have agreed, making the beer one of the more popular selections at the brewery's taproom.
Rupp’s next two projects are ancient Egyptian and Peruvian beers, both requested by the Denver Museum of Nature and Science to accompany a current exhibit on Egyptian and Peruvian mummies. Both pose unique brewing challenges.
The Peruvian beer, brewed from corn, is traditionally started by chewing the corn kernels. Enzymes in the human mouth help to break down the starch in the corn into fermentable sugars. “"Because of the scale of this brew, we can't all sit around and chew corn all day and spit it out into a vessel,” Rupp says. The health department might not be happy either. So instead, his team is finding a way to add the enzymes directly to the tanks.
Despite the technical challenges, Rupp is excited for the new beers. He thinks beer fans will like them enough that he wants to launch a new series of beers at Avery: Ales of Antiquity. “We are very much a culture that loves to learn. And people want to learn more about what the thing they're consuming came from," he said.
Nicole Garneau, Curator of Health Sciences at the Denver Museum of Nature and Science agrees. She first introduced Rupp to the rest of the team at the museum and thinks the ancient beers will help visitors connect with the Egyptian and Peruvian mummies in the exhibit. “It makes the science personally relevant,” she said. “And it allows you to experience it in a way that is completely accessible to everyone: taste. Because everyone has it.”