Sour beers are among the most complex and fascinating styles in modern brewing, unlike standard ales and lagers, which rely on clean, controlled fermentation. Sours embrace acidity, wild microbes, and time to create their signature tartness. At their core, sour beers are defined by one thing: acid production , usually driven by bacteria or wild yeast. But how brewers get there varies widely, from quick, controlled methods to years-long ageing processes. The Science of Sourness To understand sour beer, it helps to begin with what actually creates the sour taste. The defining sharpness comes primarily from lactic acid, which is produced by bacteria such as Lactobacillus , known for giving a clean, yoghurt-like tang, and Pediococcus , which can contribute deeper, sometimes funkier acidity. In more traditional brewing, wild yeast such as Brettanomyces also plays a role, adding earthy, fruity, or even slightly 'wild' characteristics alongside the sourness. This is a fundamen...
The notebook of a renegade bartender and amateur drinking enthusiast with a passion for real ale, beer festivals, microbrewing, and pubs. Relentless rants on what to drink, while quaffing, scoffing and reviewing from both sides of the bar.