Sour Beer Basics: Pediococcus, Lactobacillus, & Brettanomyces

Beer Flight (Credit: Flickr/Omid Tavallai)

Sour beers are the oldest style of beer. Prior to pasteurization and refrigeration, all beer making had unknown bacteria chomping away at the sugars making the beers tart, crisp, and refreshing. A small group of Belgian brewers continued the traditional practices of brewing leaving us with the styles we now know as lambics, geuzes, and Flanders reds.

Modern brewers now inoculate their brews with bacteria such as pediococcus, lactobacillus (which sours milk), brettanomyces, or occasionally acetobacter to create a sour tartness and impart such flavors as cherry, plum skin, mango, pineapple, or a funkiness with a smell of horse blanket or leather. The alternative to introducing these bacteria intentionally is to use a cool ship method  where the beer is moved into large, wide containers, open to the air where wild yeasts and bacteria are allowed to drop right into the beer from the natural breeze. This is particularly successful near orchards where good sour beer bacteria are in abundance.

Most sour beers on the market are aged in oak barrels for a year or more, but a faster and hence cheaper method is to produce them in stainless with the addition of lactobacillus, which can produce a tart Berliner Weiss sour overnight, whereas using brettanomyces requires several months in barrels. This is why you’ll find the Bruery’s Hottenroth Berliner Weiss, a kettle sour, on shelves for under $9 a bottle, and their Tart of Darkness marked close to $30.

This Friday, you’ll have an opportunity to meet New Belgium brewer Tamar Banner as he gives a guided tour of a flight of five of New Belgium’s sour beers at Tap & Bottle. The theme of this flight is that all of the featured brews were created with the base sour beer called “Oscar”. Oscar is a dark sour ale, basically New Belgium’s 1554 dark lager, fully fermented with lager yeast and aged in their oak foudres for acidification by New Belgium’s own house blend culture of bacteria.

The All Things Oscar Showcase begins at 5pm this Friday, April 10 at Tap & Bottle. Go. Smell. Sip. Savor. Listen. Ask questions. Develop your palate for sours. You can thank me later.

Upcoming Beer Events

  • Arizona Party Bike is now offering an all-inclusive, Tucson Craft Beer Tour hitting three downtown craft beer stops from a selection of Gentle Ben’s Brewing, Tap & Bottle, Ermanos, Borderlands Brewing Co, Pueblo Vida Brewing, and Thunder Canyon Brewing Co. The all-inclusive ticket price will be $39/person, which includes samplers, tax, gratuities, and transportation provided on the Arizona Party Bike. Tour times will be at 2pm on Saturdays and 6pm on Wednesdays, to be expanded as demand grows. Visit for more information
  • 2015 Tales and Ales Benefit Dog Wash happens this Sunday, April 12th at Barrio Brewing Co.! This event raises funds for the Tucson Roller Derby and the Humane Society of Southern Arizona. From 11:00 am – 4:00 pm, derby girls will be washing dogs for just $15 ($12 if you bring your own towel)! More info.
  • Borderlands Bacchanal, a two day Arts and Music Festival! The two day celebration of beer, music, film, art, revelry and good times kicks off at noon this Saturday, April 11th featuring live bands, a local film festival, stand up comedy, and a long list of local artists. Admission is free! More info.

Craft Beer Betty, aka Sarah Ritchie, is a craft beer evangelist as co-founder of Tucson Girls Pint Out and board member of Craft Tucson. Find her on Twitter and Instagram as @craftbeerbetty.