Sour beers are one of the most popular beers in the craft beer world at the moment. Local and international brewers have been serving up sours over the past few years, and they don’t seem to be going away. These beers are tart, fruity and occasionally funky, but are by no means new — sour beers are some of the oldest styles of beers in history!
Before humans mastered the art of sterilization and pasteurization, most beers had a sour taste to them—this is due to natural bacteria that integrated with the beer during the brewing process. Nowadays, sterilization and pasteurization are common practices, so brewers can play with the two to create unique flavours and experiment with levels of tartness, funk and fruit.
The traditional sour, popularized in Belgium with historic, world-renowned breweries such as Cantillon, Boon, and 3 Fonteinen, is made through a process called “spontaneous fermentation”. In this, the wort (grain/water mixture used in brewing) cools overnight in shallow, open-air pans called “coolships.” Kind of similar to the way that “terroir” affects the flavours of wine grapes, natural yeast, microbes and bacteria from the surrounding air collect in the wort to create lactic acid.
The resulting beer is then placed in breathable wooden barrels—again, similar to wine—so that it can breathe and absorb more bacteria. This aging is what perfects the sour taste and flavour complexity of the beer, and it’s not uncommon for beer to spend a lot of time aging in barrels—much unlike most craft beers on the market today that are brewed to be consumed fresh.
Kettle sours are much quicker to make than a traditional sour, and are thus more widely seen in the Alberta craft beer world. This method is used to create beer styles like the Gose and Berliner Weisse, which typically have less complex flavours but make for a refreshing summer beer. “Kettle” refers to the brew kettle, meaning the beer is soured in a stainless steel mash tun and fermented in a similar tank—not a barrel like the traditional sour.
Instead of a traditional mash, kettle sours undergo a “sour mash.” Basically, instead of boiling the beer-to-be and then cooling it to ready it for the addition of yeast, the liquid is boiled, cooled, and dosed with lactobacillus, which gives it that tarty flavour. The wort mixture then chills for a few days in the “kettle” while the liquid sours. Once the desired level of tartness is achieved, the normal brewing process is resumed—boil; add hops; cool wort; add yeast and let ferment.
Brewers can continue to be playful with their sours with the addition of dry-hopping or adding fruit to either balance out or enhance the beer’s tartness.
Get hooked on sours today
City Cellars has a great selection of locally-made, Alberta sour beers to get you started on this beer style. If you’re more of a wine drinker, sour beers are the perfect foray into the craft beer scene. And once you’re hooked, you’ll start seeking out sours at every turn!
Stop by the store, contact us by email or phone us at 780-420-1650 to find out what Alberta craft sours we have in stock today!