Sour beer is a type of beer that is brewed with wild yeast or bacteria strains such as Lactobacillus or Pediococcus. This type of beer is intentionally soured to give it a distinct tart or acidic flavour that is different from traditional beer styles. Sour beers can range from mildly tart to intensely sour and may have flavours reminiscent of fruits like cherries, raspberries, or citrus. Sour beers can be brewed in a variety of styles, including Berliner Weisse, Gose, Flanders Red Ale, Belgian Saison and Lambic.
Some sour beers are also aged in oak barrels to develop complex flavours and aromas. Despite its distinctive flavour, sour beer has become increasingly popular in recent years and can be found in many craft breweries and beer bars around the world.