If you’ve been paying attention to the Alberta beer scene lately, you might have noticed a “new” style of beer creeping its way into popularity—Sour Beers. In Calgary, Dandy Brewing has a sour for every season and Wild Rose Brewery has the Cowbell Kettle Sour. In Edmonton, Situation Brewing has the WTF Blood Orange. And in Lacombe, Blindman Brewing has a range of kettle sours as well as barrel-aged sours. They’re distinct, fruity beers with a unique tartness—but what exactly goes into making a sour beer?
Sour beers may seem new to the Alberta brewing scene, but they are actually some of the oldest beers in history. Before humans understood the concepts of sterilization and pasteurization, most beers had a sour taste to them—all thanks to the natural bacteria that found its way into the beer during the brewing process. Now, brewers understand these concepts and can play with them to create the taste they’re looking for.
There are two main modern ways to produce a sour beer, the first being Traditional Sours. For this kind of beer, the wort (the grain/water mixture used to brew) goes through a process called Spontaneous Fermentation, where the wort is left to cool overnight in shallow, open-air pans called "coolships". During this time, the natural yeast, microbes, and bacteria from the surrounding air collect in the wort and create lactic acid. The beer is then placed in wooden barrels that allow it to breathe and absorb more bacteria, and that’s what gives the beer its sour taste. It’s not uncommon for brewers to spend years, if not decades, perfecting the natural microbes in the air of their brewery to get the taste they want.
The other type of sour beer is the Kettle Sour. As the name implies, the souring process happens in a kettle and not from exposure to air and natural microorganisms. In this style, a form of lactic acid bacteria is added to the kettle during the brew to give the beer its tartness.
This might not sound like the most enticing of beers, but it’s similar to what goes into making yogurt, or sourdough bread—both of which are delicious. Many brewers also add fruit into the mix to help balance out the sour flavours. They’re a little strange to get used to at first, but once you do, you’ll find yourself coming back for more.
- Alexander Sorochan