Sour Beer

What is Sour Beer?

Sour beer is a beer that has an intentionally acidic or sour taste. Sour beer styles include Belgian lambics and the German gose and Berliner weisse.

Sours are usually made by intentionally allowing wild yeast strains or bacteria into the brew. The most common microbes used to make sour beer are the bacteria Lactobacillus.

Depending on the process employed, the uncertainty involved in using wild yeast may cause the beer to take months to ferment and potentially years to mature (see Belgian lambics). However, modern sour beers can be created within a typical timeframe for ales.

Origin Story

At one point in history, all beers were, to varying degrees, sour because there were many naturally occurring bacteria present in beer. These living organisms resided in the beer throughout the fermentation process, and their presence produced a sour or funky flavour.

As refrigeration and pasteurization technologies evolved and became more prevalent in the mid-nineteenth century, sour beers virtually disappeared.

However, the first intentionally sour beers were lambics, brewed in Belgium from the 18th century to this day.

The Germans also embraced the sour taste by making their Berliner weisses sour on purpose through controlled fermentation with lactic acid bacteria. What used to be an unintentional side-effect became the trademark of Berliner weisse.

Nowadays, sour beers are gaining popularity all over the world, especially in the US craft beer market.