In the ever-fluctuating world of trendy beers, the latest contestant is sour beers. It’s an odd entry given the word “sour” is usually avoided as an adjective in beer lexicon.
When categorized, it is not the one trick pony it is often perceived to be, with most people today not knowing the difference between a gueuze and a gose. Despite being relatively new to most North Americans, sours have been around for hundreds of years, harking back to the days of wooden vats, inadequate sanitation, and microbiological nescience. Its current revival is being nurtured in craft breweries, as brewmasters resurrect long lost recipes using modern brewing techniques.
In reality, sours represent a whole genre of beers. They come in a diverse collection of aromas, colours, carbonation levels, alcohol contents, pH levels, and flavour profiles. Most are barrel aged or have added fruit, sending the category in a plethora of directions. However, one constant dictates a true sour; it has been made with wild yeasts and/or bacteria that yields the tart or acidic notes in the final product.
To achieve that result, brewers of yore usually let wild organisms inoculate the wort through open-air fermentation. The outcome was often unpredictable, so these beers spent months or years aging in barrels and young and old versions were often blended. Found mostly in the breweries of continental Europe, especially Belgium and Germany, they are still made this way today.
The main catalysts for production of these beers are certain yeast strains within the Saccharomyces genus, commonly Brettanomyces, and other wild microbes like Pediococcus and Lactobacillus. Brewers also experiment with wild yeasts, literally those found outdoors.
Today many “wild” organisms can be purchased from labs, and fermentation is more controlled to yield the desired flavour profiles. The traditional descriptors of sours usually sound completely unappealing: funky, barnyard, horse blanket, sweaty socks, and more. However, through centuries of practice, the famous brands have survived to become some of today’s most sought-after beers.
The time, effort, space, and expense required for barrel aging is often prohibitive for most new craft breweries, so this is where the kettle sour steps in. By souring the beer in the mash tun, it can be produced in about the same time as a regular beer, with no need for barrels. Often fruit is added to make these beers more palatable.
While most breweries in North America choose this approach, there are a few committed to traditional methods. In Alberta, two breweries in Edmonton stand out by creating nothing but varieties of sours and other wild fermented beers. Trial and Ale and The Monolith (a dedicated barrel fermentation project of Blind Enthusiasm) have begun brewing and aging unique beers that rival those from Europe. Expect complex, nuanced beers in a wide range of aromas and flavour profiles, subtly astringent with some citric characteristics amidst almost vinous or cidery notes. Other breweries have recently started barrel fermenting projects alongside their regular lineup.
Because all sours are not created equal, they get broken down into a few different categories, depending on ingredients, flavour profiles, production methods, and other factors. Most are wheat ales, some using unmalted wheat.
Search out the European classics and local interpretations from the hundreds available in this market:
Berliner Weisse – Low alcohol (< 4 percent ABV) with a lactic sourness. Traditionally served with fruit syrups in Germany, now breweries add the fruit for you. While no true German brands are available here, look for Ribstone Creek Raspberry Berliner Weisse and Blindman’s Florida Weisse series.
Flanders Red Ale – Reddish-brown with flavours of plum, raisins and currants. Aged for long periods and produced through a blending of young and old beers. Hailing from western Belgium, you can find Duchesse de Bourgogne and three classic examples from Rodenbach brewery in Alberta.
Oud Bruin– A darker adaptation of the above with more caramel notes. VanderGhinste Oud Bruin is a classic Belgian example.
Lambic and Fruit Lambic – Brewed only in the Senne Valley near Brussels with wild airborne yeast and aged until fermented. Rare examples from breweries like Cantillon, Boon, Drie Fonteinen, and Lindemans appear infrequently in this market. The more prevalent low alcohol Fruit Lambics are made by adding juice from apples, peaches, raspberries, cherries, or cassis to change the flavour profile.
Gueuze – Fermented with wild yeasts, aged for years, blended, then bottle conditioned. Tart, citric, and almost cider-like. Drie Fonteinen and Tilquin are available here.
Gose – Originally from Germany, featuring coriander and salted water. Modern renditions usually add fruit. Look for both versions of Wild Rose’s Ponderosa Gose or Situation Brewing’s WTF (Wild Type Fermentation) series.
Mixed-Fermentation Sour Beer – This is what can happen when multiple yeasts, bacteria, fermentation processes, and barrel aging meet, making each beer a unique release. Search out the beers from Trial and Ale, Blind Enthusiasm/The Monolith and others.
Kettle Sours – Many local breweries are now making sours this way, mostly as seasonals. Some will make multiple renditions from the same recipes by adding different fruit. The most prolific seem to be Zero Issue, New Level, Odd Company, Cabin, The Establishment, Blindman, Dandy, Big Rock, Railyard, Analog, Alley Kat, Canmore Brewing, Medicine Hat Brewing, Town Square, Hawk Tail, and Banded Peak, plus a few more.