As sour beer becomes more popular, more producers are foregoing traditional kettle-sourcing processes to inoculate their brews with wild yeasts, often found in unusual places. Pennsylvania-based Levante Brewing Co. has developed a yeast called Philly Sour, which was found on the bark of a dogwood tree in a local cemetery and is now sold worldwide.
“I don’t know if the enthusiasm for hops will ever really wane, but with so many beer options available, there is definitely the space for some breweries to focus more on other ingredients,” said Gerard Olson, owner of Forest & Main Brewing Co. in Ambler, PA. That brewery every spring forages for yeasts from flowers on the property and uses them for that season’s saisons.
The Philadelphia Inquirer calls Philly Sour (and Norwegian yeast called kveik) “beer’s mostly unsung heroes.” The professor who isolated the Philly Sour yeast, “sends students into the neighborhood with Ziploc bags to collect samples, leaves, scrapings from bark, and other materials that might have yeast on them. Those materials are tested for fermentation.”
Read more (The Philadelphia Inquirer)