According to a report by ABC News, Emeritus Professor Raul Cano of the California Polytechnic State University, originally extracted the yeast a decade ago, along with more than 2000 different kinds of microscopic creatures.
Today, Cano uses the reactivated yeast to brew barrels of pale ale and German wheat beer.
"You can always buy brewing yeast, and your product will be based on the brewmaster's recipes," said Cano. "Our yeast has a double angle: We have yeast no one else has and our own beer recipes," he added.
The beer received good reviews at the Russian River Beer Festival and from other reviewers.
The Oakland Tribune beer critic, William Brand, said that the beer has "a weird spiciness at the finish," and The Washington Post said the beer was "smooth and spicy."
Part of that taste comes from the yeast's unique metabolism.
"The ancient yeast is restricted to a narrow band of carbohydrates, unlike more modern yeasts, which can consume just about any kind of sugar," said Cano.
Eventually, the yeast will likely evolve the ability to eat other sugars, which could change the taste of the beer.
Cano plans to keep a batch of the original yeast to keep the beer true to form.
"We think that people will drink one beer out of curiosity," said Cano. "But if the beer doesn't taste good, no one will drink a second," he added.