How Acidic Is A Sour Beer Really?

For those of you who don't like sour things– Warheads, fresh lemons, kombucha, cranberries, and so on — it's time to head out! Those of you who do love the power of sour, welcome! At this point, hopefully, you've heard of sour beer. According to Vine Pair, sour beer is old — older than the IPA you're sipping on or that pilsner you chugged. All beer used to be sour beer because our ancestors didn't pasteurize anything (a shiver-inducing statement for sure), so wild yeast and bacteria ran amuck everywhere, giving our beverages a notable vinegary, tart flavor.

Mellow Mink Brewing claims that archaeologists have discovered that we can date beer back to at least 7000 BC, but all that wild yeast used to brew it meant that it always turned out a bit sour. But sour beer is still enjoyed today! There is a complexity that comes from making beer with wild yeast strains that attracts customers. And with people lining up out the door for a good, puckering experience, it's time we worked out what makes the acidity in sour beer really pop.

You've got to look at the pH

We gently touched upon it above, but let's reiterate: while non-sour beer, which is currently the most common kind of drink, uses a controlled yeast for consistency, sour beers are fermented using acid-producing bacteria and wild yeast, thus the powerful tart flavor you'll get in sour beer (via Craft Beer).

But how acidic can sour beer be? Well, Food & Wine says that it ultimately will come down to the number of hydrogen ions floating around. The more hydrogen ions, the more acidic your sour beer will taste. In the most basic of terms, the way to see how acidic sour beer really is involves measuring the pH, aka "potential hydrogen." Craft Beer & Brewing states that if the pH numbers below 7, the beverage is more acidic than water, whereas higher numbers are more alkaline. Food & Wine says that single-strain yeast beers like lagers tend to fall between 4 and 5 in pH, whereas sour beers can have a pH value of 3! So, how sour can sour beer be? Pretty sour indeed!