what is sour beer?

Back in 2017 I stopped producing anything with laboratory yeast. No IPA, no stout, no pilsner, really no style of beer you’d recognize from your grocery store shelves. Before that I would call the lab in California and have them next-day air me yeast the day before brewday so it was healthy, predictable, viable and ready to make a beer that tastes like a beer style.

Now 100% of the sugars in my wort (the sugary extract that comes out of my brewhouse on brewday) are converted to alcohol, acid and esters by native, or feral or local or indigenous yeast and bacteria. Yeast and bacteria that happen to make their home where we make our home in Historic Downtown New Braunfels-just floating around on the air and chillin’ near the river. Much like kombucha, my multiple strains of yeast and bacteria work symbiotically to create a Mixed Culture Beer that is funky, dry, refreshing and makes you pucker a bit.

I still drink beers brewed with pure culture yeast (Live Oak Pilz is always in my fridge) and still appreciate them for what they are and the role they’ve played throughout brewing history. But as an artist, I’m not interested in producing any particular style of beer. A style of beer is, by definition, someone else’s art that they created and other brewers have attempted to improve or just keep up with. At best, every subsequent brew is a brew-by-numbers copy of the original recipe. Artistically I find that uninspiring. Again, I’m happy to drink those beers, I just don’t want to be the guy making them. 

So when someone asks if I brew sour beer, the answer is no. No, I don’t. 

I’ll try to explain why. 

Ever had a sour wine? How about a sour fruit smoothie during Dry January? Ever seen sour buttermilk pancakes on the menu? Was there ever a Super Bowl ad for Sour Coke? Red Bull is way more sour than any beer I’ve ever shoved in my face. No one markets their low pH products as sour unless it’s beer. Or candy. 

What is a Sour Beer?

For beer we measure the acidity of a liquid two ways; Titratable Acidity, which I’m not gonna address today, and Ph. Ph is the measure of the concentration of the free hydrogen ions on a scale of 0-14. Anything above 7 is alkaline and anything below 7 is acidic. Technically all beer is lower than 7Ph so has acid present and could be categorized as sour. The acid dries the body, engages more taste-buds and balances some of the residual sugar left behind in a beer fermented with pure culture yeast. Somewhere around 4Ph we start to notice that the beer is sour. The other components the brewer brings to the recipe will affect your perception of the acid. More hops, alcohol and more residual grain sugar are the obvious ones. Even spices, roots, fruits and (dammit) lactose milk sugar are used to create a counterpoint to acidity. So you may have two beers with the same Ph and one will taste much more sour than the other. Sorry, there’s nothing I can do about that, it’s just science. 

A few types of Sour Beer

Kettle Sours are produced by adding bacteria pre-boil while sitting in the brewer’s kettle. These would include BerlinerWeiss beers and Goses, although traditionally they weren’t all fermented this way. 

Mixed Culture beers are produced by fermenting with more than one yeast strain and usually also with bacteria. These would include some Saisons, all lambic beers and spontaneously fermented beer, typically most oak-aged beers and a lot of beers that say Brett on the label or in the name. 

The Belgian Oud Bruins and the Flanders Red Ales are kind of a hybrid of the two with a focus on acid production and mixed culture fermentation. Usually these are done in stages so they are a little different than mixed culture fermentations. 

If there are organic acids present in the beer (as there are in wine or fruit juice) your tastebuds will perceive that as sour. There are many more than one acid that can be present but most sour beer will contain lactic acid in quantities high enough to make you pucker. You’ll see acetic acid pretty regularly also. With the addition if fruit, malic and citric acid will also put on their dancing shoes. 

For me, I define Sour Beer as a beer produced with sour as the endgame. The flavor is concerned with pucker for pucker’s sake and is produced using techniques to enhance the sourness, purposefully lowering the Ph. Usually the body, the booze and the hops are kept light and there is residual sugar that attempts to balance the acid somewhat, making it more chuggable and heavier on your palate. The sour is one-dimensional and encouraged to steal the spotlight like some insecure diva. 

Labeling these beers is the tricky part. Brewers aren’t very adept at staying in their lanes so the term sour has been thrown around like a kitten at a 3-year-old birthday party. There is no accepted standard for the process to make it sour or the final measurement of how sour it is. Labels say all kinds of things and deciphering them takes some genius. It’s the wild west of wild fermentation out there. 

How do you make it Sour?

Typically by adding lactobacillus bacteria at some point into the fermentation. This bacteria eats a percentage of the sugars and converts them to lactic acid. 

For ‘kettle sours”, which will represent most beer with sour in the description and almost all sours in a can, this is done in the brewkettle instead of a fermenter. The unfermented beer (wort) is transferred to the brew kettle and heated to boiling or near boiling to kill any life that was living on the grains. It’s then cooled and left in the brewery’s kettle at around 110 degrees and a healthy, bioengineered strain of bacteria is added to maximize the lactic acid production. During this stage Oxygen is the enemy and many of these beers will showcase baby diaper or throw-up aromas due to sloppy brewing techniques. After a period of hours (sometimes days) at warm temperatures the bacterial fermentation is complete and the brewer will then boil the wort to kill the bacteria, add hops and continue skipping down the Yellow Brick Road to their fermenter. They then pitch laboratory yeast and ferment the beer like they would with a normal beer, with the exception of the additional lactic acid hanging around. 
Some of the more traditional German brewers would split the batch of wort from the brewkettle and use a ‘souring tank’ for half of the brew. They allow this tank to get bracingly acidic while the other tank ferments with a pure culture yeast. They then blend both tanks together to create a pleasing level of lactic sourness. 

For mixed culture beers (like mine), the beer is made sour after boiling as part of the normal fermentation process. This causes the bacteria to compete for sugars with the yeast strains, which balances the acid and creates new flavors and complexity. Fermentation can take place in steel and/or in oak barrels and can vary from months to years. Some of this acid will also be produced by Pediococcus after a few months and even Brettanomyces yeast as much as years later. With extended aging in oak (or brewer mistakes) another bacteria, Acetobacter, will convert alcohol to acetic acid in the presence of oxygen. Acetic acid is a bold acid that is extremely sour and tends to overpower everything else even in small amounts. Spontaneous fermentation also runs the risk of oxygen waking up some bacteria you don’t want. Again the baby diaper or throw-up aromas. 

You can also buy acidulated malt to brew the beer that basically has acid on it. Boooring. Shitty brewers can (and some do) also add food grade acid directly to a fermentation tank and just ‘make it sour’. To be fair, many winemakers, especially those in warm climates, will use this trick to keep their acidity on point for the style of wine they are making. I don’t appreciate it at all when they do that either. 

The soda companies just drop a mess of citric acid into their products and no one seems to care. But we already know those things will kill us, right?

Why is my beer not a Sour?

So to start, I think it’s fair to say that years ago my beer was a Sour. As early as 2012 I was experimenting with adding wild yeast and bacteria to a hefeweizen, dunkelweizen and a weizenbock. I wanted to take the experience of that beer and just add a pucker to it, enhancing the flavor and drinkability. Also because sour was weird and cool and I wanted to play in that sandbox. But I was a blind man (or a toddler in a sandbox) with a long paintbrush. As much as I might have been able to produce something that resembled a liquid Jackson Pollack, I was really just flinging paint on a canvas, not producing art. 

Looking back now I was just trying to add acid to beer. While I was using a mixed culture and creating a dry, effervescent beer, I didn’t fully understand the role all the components played in creating what got poured into your glass. 

Over the years I’ve refined my style, broken down the constituent pieces of the brewing and fermentation process and now have a cohesive story to tell through the beer I produce and the bottles it rests in. I start with your experience and work backwards to construct a process Hell-bent on crafting a thoughtful end product.

As the soul of the brewery, Blondine is a critically important part of my brewing portfolio. What began life in 2015 as a hefeweizen that ‘went sour’ is now a bone-dry, crisp wheat beer with subtle nuance and a dancing delicacy. It’s the beer that rests in barrel to create 4-6 fruited sours each year and the beer that rests in steel to create their spent fruit counterparts. It’s important, it matters. And it’s more than just sour. 

To brew Blondine I start with 85% white wheat/15% pilsner and mash at low temps to give the slower yeasts something to much on over the years they spend in barrel or bottle with the beer. I boil 90 minutes for complexity and to fully incorporate hop acids into the wort. In Mid-2019 I began adding 40% aged hops to the boil from my supply of 4-5 year old hops that have aged in the TX weather in my outside storage. This is one way that I limit the activity of the acid-producing bacteria without making a bitter beer, which I can’t stand. My target IBU (a measure of how bitter the beer is) is around 15 but with the aged hops your perception of the bitterness will be down near 10. Translation: you can’t taste it. Lactobacillus doesn’t like either hops or alcohol and the presence of either in high quantities will slow its growth so we might be soul-mates. 

Fermentation is where Blondine matures and it’s true depth of flavor really comes from. The mixed culture that ferments all of my beers used to complete primary sugar conversion in 6-7 weeks. Years later it now completely finishes in 3-4 weeks with a more balanced and subtle range of flavors and aromas. And that’s only the very beginning of the life-cycle for this beer. By controlling the temperature after primary fermentation and bottle-conditioning I can extend that secondary fermentation for years, depending on what I’m making and targeting with the final beer. There is still sugar left in the beer and energy left in the microorganisms and it’ll be years before they’re both exhausted. When we release Blondine in kegs and bottles it’s typically 8 weeks old and, like an obnoxious kid throwing rice on the floor at Chipotle, it has quite a bit of growing up to do. After 2-3 years in the bottle, a silky cohesiveness opens the beer in new and noteworthy ways. The yeast becomes more present with funky, Earthy notes and the acidity is softer and more balanced. It evolves ya’ll. Everyone’s opinion is correct so whether you like infants, like my wife, or don’t, like me, Blondine has you covered if you invest some patience and thought. 

Normally Blondine will ferment in steel first and then I transfer to barrel second but sometimes I’ll ferment directly in barrel just to create something a little different. Every Fall I go through the brewery and select 8-10 barrels of Blondine for my annual blend. Each barrel is unique and brings it’s own personality to the complexity of the final blend. I’ll add 4-week old Blondine to the blend to extend the bottle maturation and slap a Heavenescent label on it. This is the most complex version of Blondine and one that may develop gradually in arousing ways for many years in the bottle. 

Refermentation with fruit adds additional layers of flavor. I’ll select barrels based on character of the fruit I’m using. If the fruit is bright and aromatic like peaches, I’ll select a more funky, yeasty barrel. If the fruit is highly acidic like raspberries, I stay away from the really sour barrels. 

Then I contact the fruit with barrel-aged beer twice. The first press is half the volume of beer and extracts the juice, the jamminess and the acid. The second press extracts the tannins of the skins, a brighter fermentation character and adds a deeper complexity than one big press would. These are the Saison de line of fruited beers. 

After the second press, I ferment a very young batch of Blondine directly on the spent fruit for 3-4 weeks to extract the essence of the fruit and the tannins from skins and seeds in light and delicate ways. These are the Blondine de line of spent fruit beers. 

I also age Blondine on fruity hibiscus flowers for Funkromancer. I’ll dry-hop it with tropical hops for Hopfenstopfen. Or blend it with a dark beer for Bier No.217. Once I even boiled it with green coffee beans and Mexican sugar. 

So you see Blondine gets around. 

Call it Mixed Culture Beer

Sour doesn’t tell the whole story of a Mixed Culture Beer. It’s like saying that your car is red when it’s actually 4 colors and its only 30% red. People like to put things in cute little boxes that they can compartmentalize and understand, but the types of beer I make just don’t fit. You wouldn’t call yourself Native American if you only have 3% Cherokee in your family tree. (maybe when you’re applying for scholarships but not on Indigenous People’s Day). But that’s what we like to do with sour beer. 

I mean Hell, if you’re a Dallas Cowboys fan you cheer for the Patriots around 0 percent of the time. We don’t like when things don’t fit their box but that’s exactly what my beer does-or doesn’t do. It’s all over the place. It pairs with fish, it tastes like wine, it makes you salivate, it goes down easy, it’s intended for thoughtful inspection, it holds up to steak, it warms your belly and it refreshes your soul. 

Plus, I just don’t like it. Calling it sour doesn’t take the time to give credence to the whole picture and the effort behind it. If you took a 1” square of Picasso’s Girl With The Mandolin you’d think it was part of his grey period. Only by zooming out can you realize it was one of the most influential works of his Cubism Period.

Really I’m just asking you to zoom out. See it all, drink it all. 

Thanks for Drinking, 

Kelly KFM Meyer

Leave a Comment

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s