What is sour beer?

Sour beer dates back to the early days of brewing. Nearly all types of beer — both lagers and ales — used to be sour before pasteurization and sterilization were things. If you take the name too literally, you may even (wrongly) assume the beer has gone bad. Fear not. Even the more pungent ones can be profoundly exhilarating.

Sour beers today are intentionally tart and acidic, and made with wild bacteria and yeasts (whereas, more common beers are made in sterile environments with specific yeast strains). These include souring agents, such as Lactobacillus (a bacteria most commonly found in yogurt), Pediococcus (a bacteria often used for acidity in Belgian beers) or Brettanomyces (a wild yeast also known as “Brett”).

These funky micro-organisms produce lactic acid and acetic acid, which contribute to the sour flavour profile of the beer. The brews can also be flavoured with fruits and spices to balance all that acidity and lend their own robust tasting notes. Some sour beers are even aged in barrels after fermentation and also vintage-dated.

How do sour beers taste?

Sour beers can vary greatly in terms of taste, aroma and intensity of sourness. Some sour beers have a subtle tartness, while others can be deeply acerbic and lip-pursing. Their flavours range from fruity and funky to earthy and wine-like, with aromas of berries, stone fruit, citrus, balsamic vinegar, kombucha and sourdough bread, among others. While no two sours are exactly alike, the most common characteristics that define this style are:

Acidity: Sour beers typically have a noticeable acidity, which contributes to their tartness.

Complexity: Sour beers often show off complex flavours beyond just sourness, including fruity, funky, earthy, vinous and even oaky notes.

Balance: Despite their sourness, well-crafted sour beers are often balanced with other elements, such as malt sweetness, hop bitterness or the flavours that develop while the beer is aging in barrels.

Dryness: Sour beers tend to have a dry finish, which can enhance their refreshing qualities.

What are the most popular styles of sour beer?

Despite their defining characteristics, sour beers span an impressive range of styles, each with its own interesting flavour profile. Among the most popular are:

Lambic: A traditional Belgian style of sour beer from the Senne River, near Brussels, that is spontaneously fermented using local wild yeasts and bacteria. Lambic beers are often aged in wooden barrels, producing a complex flavour profile with a pronounced sourness and funky, earthy (and sometimes fruity) tastes.

Gueuze: A blend of lambic beers of different ages, typically a mix of young and aged, gueuze undergoes refermentation in the bottle, resulting in natural carbonation. This style exhibits a sharp, complex sourness, with flavours that can range from tart to funky, often with a dry finish.

Flanders red ale: Also known as Flemish red ale, this is another Belgian style of sour beer originating from the (you guessed it!) Flanders region. It undergoes a mixed fermentation process that includes both wild yeast and lactic acid bacteria, resulting in a malty flavour with balanced sourness and complex flavours, including fruity, vinous and caramel notes.

Berliner weisse: This is a German-style sour wheat beer known for its extra-refreshing and tart qualities. It’s typically low in alcohol, light in body and highly carbonated. Berliner weisse often features a clean, lactic acidity that provides a refreshing and crisp character. It can be enjoyed plain, but it’s traditionally served with flavoured syrups, such as raspberry or woodruff, to balance the sourness.

American wild ale: These craft brews often draw inspiration from traditional Belgian styles, but showcase a distinct American twist. American wild ales can range from light and refreshing to bold and funky, with a diverse range of sourness and flavour profiles.

How to serve sour beers

In general, you want to serve sour beers cold (but not ice-cold), between 7 C and 10 C, or after a few minutes out of the fridge. Like other aromatic beers, they should also be poured slowly and at a 45-degree angle. And they should be sipped from a glass — not chugged from a can or a bottle.

Sour beers often evolve as they warm up, so pay attention to how the flavours and aromas change as the beer reaches room temperature.

Special glassware, such as tulip glasses, goblets or snifters, also enhance their aroma and let you appreciate their colour and carbonation.

Best foods to pair with sour beers

Think of a sour beer food pairing as anything that could use a squeeze of citrus: fresh lemon, lime or orange. Here are some great matches.

Fruity and spicy foods: Sour beers with fruit infusions or complex fruity flavours can pair well with dishes that have sweet and fresh or spicy elements, such as Beer Bean Tacos with Quick Pickled Onions or Thai Chicken Curry with Squash & Ale.

Cheesy foods: Sour beers pair well with a variety of cheeses. The acidity of the beer can cut through the richness of creamy cheeses, such as Brie or Camembert. It can also complement tangy and aged cheeses, such as chèvre, Gouda or blue cheeses. Consider pairing a Flanders red ale or a gueuze with cheese plates or cheese-based appetizers, such as Cheese Twists with Hot Honey-Lager Drizzle.

Seafood: The bright acidity of sour beers can give seafood dishes a refreshing contrast. Try pairing a Berliner weisse or a fruit-infused sour beer with oysters, ceviche, grilled fish or other seafood, such as this Radler-Marinated Shrimp & Yogurt Sauce.

Salads: Sour beers can be a punchy choice to liven up salads and light appetizers. Their acidity and bold flavours can complement the freshness of salads with vinaigrette dressings or citrus-based ingredients, such as this Green Bean, Fried Hazelnut & Blonde Ale Salad.

Desserts: Sour beers can be surprisingly enjoyable with fruit-forward desserts, such as this Barrel-Aged Ale, Nectarine & Raspberry Cobbler. Consider pairing a fruit-forward sour beer with berry tarts, citrus-based cakes or creamy desserts with a tangy element.