Beers that are sour rather than bitter or sweetly malty are all the rage these days, but even many of the category’s most devout advocates aren’t entirely sure what they’re all about. In fact, centuries ago, sour beers were the norm rather than the exception, since without isolated yeast strains in the brewery, fermentation was effected by whatever yeast (and sometimes souring bacteria) happened to float in the window.
Modern sours tend to rely on very specific micro-organisms like Lactobacillus, the heavy lifter of sour beer, which is more typically found in yogurt. Lacto, as it’s commonly known, can be introduced early, as in the process known as kettle souring, or added alongside brewer’s yeast and other yeast and bacteria during normal fermentation to make what’s known as a “mixed fermentation” beer. Either way, the result is flavours that are tart but not vinegary or harsh — and with enough unexpected tasting notes to drive even your most devoted oenophile pals nuts.
FOUR SOURS TO SEEK OUT
1. Bench Citra Grove (6%)
From one of Ontario’s most exciting young breweries comes this mixed-fermentation marvel that is delicious as-is, but will also develop in the bottle long after packaging.
2. Four Winds Nectarous (5.5%)
Made tart and complex by Lactobacillus, this is also dry-hopped — meaning hops are added after as well as during the boil — and filled with tropical fruit flavours.
3. Exchange Golden Ale (7.6%)
Another impressive young Niagara brewery, the Exchange specializes in oak-barrel conditioning, as with this dryly vinous, barely tart ale aged in French oak.
4. Rodenbach Vintage (7%)
A limited-edition bottling of a famously fruity-tart-fascinating Flemish red ale, this is bottled from a single foeder, or wooden vat, after two years of aging.
INTRODUCING THE MONOLITH
Years in the making, The Monolith is the newest project from Edmonton’s Blind Enthusiasm, designed from the ground up to be a temple to sour beer. It combines the alchemical magic of spontaneous fermentation — head brewer Doug Checknita formerly worked at the Belgian lambic legend Cantillon — with the science of modern microbiology. Their spontaneously fermented stuff is still a year or three away from being ready, but early barrel-soured beers are in limited release this fall.