11

SIMPLE WILD

“Just because you’re going funky doesn’t mean you shouldn’t be just as careful as you would with a ‘clean’ beer.”

The last thing we want to simplify, before we get back on our journey to complicating everything, is the ultimate return to basics. You see, everything else in this book has been about how to make the best beer as simply and cleanly as possible, but that has only been the story of beer for the last briefest blip of history.

Before we got all clean and selective with our fermentations, many of our beers were fermented with a mélange of yeasts and bacteria. Some of these traditions are still alive, most notably in the lambic of Belgium, but as science has increased our understanding about what’s responsible for the various weird and funky flavors and aromas, brewers have exerted more and more control over what ends up in their wild beers.

Wild fermented beers can be, and usually are, an acquired taste. In Denny’s case, and for many other people, you don’t get it at first sip, but there’s something there that’s intriguing enough to keep you coming back. It’s a quest. You want to find out how you can hate it at the same time you’re starting to love it. And then one day it happens—you get past the sourness and funkiness to the underlying complexity. And the next thing you know, that’s exactly what you’re trying to get your beer to taste like.

Before we get into this chapter, we just want to point out this is going to be a fingernail-thin overview of a very complex subject. We’re here to get you started. You may find yourself saying, “Wait, I know there’s more.” Buddy, you don’t know the half of it. Fortunately, Brewers Publications has you covered with Michael Tonsmeire’s encyclopedic American Sour Beers.1

WILD DONE SAFELY

The first and, to our mind, most important rule about “wild brewing” is don’t get lazy! A number of homebrewers tend to treat their funky beers with a more lax and carefree approach to sanitation, cleanliness, and fermentation control. Trust us when we say that’s a bad idea.

Just because you’re going funky doesn’t mean you shouldn’t be just as careful as you would with a “clean” beer. Remember, most critters that would love to take up residence in your sweet, sugary pool of wort make for bad flavors. Even the good funkmeister-type yeast will go wrong if their health and environment isn’t cared for. In many ways, these less brew-savvy organisms need even more of our help to make sure they do what we’d like!

In other words, keep clean, keep sanitary, and keep your temperatures in check. Just like you would when making a clean beer.

There’s also the flip side to this—your equipment aftercare. The microorganisms we’re using to funkify the beer, namely members of the Lactobacillus and Brettanomyces genera, are incredibly impactful at even low levels of dosing. Allowing a few cells to slip into your next batch of beer (whether into the fermentor or keg) can, over time, lead to replication and the production of funky beer in what was supposed to be your IPA. It’s great if that’s what you want, but not so much if you’re hoping to serve a bright, hoppy, clean-tasting beer. We recommend going full scorched-earth on your gear and hit it with iodophor after a thorough cleaning. We also dedicate anything plastic, like tubing or bucket fermentors, specifically to sour/funky stuff to reduce a chance of cross contamination.

The final thing to do for “safe” wilds is to shop around. There are a number of suppliers of pure cultures of bacteria and wild yeasts. When we first started brewing there were so few funky cultures on the market you could easily count them on one hand. You could have been forgiven for thinking that there was only one Lactobacillus and a few Brettanomyces species in the world. Nowadays, with microbiologists (turned brewers) deciding to help the rest of us out and suppliers like The Yeast Bay and Bootleg Biology cropping up all the time, there’s no end to your options. Play with them, you’ll be surprised!

WILD INOCULATION

OK, fine, you want to really go au naturel, to go really, truly wild. Let’s talk about this. We want you to be safe and have fun. Probably the most famous wild brewing tradition is lambic brewing, so let’s start there.

Lambic is produced from a fairly complex “turbid” mash scheme that, traditionally, helped deal with the less than perfect malt and grains of the time; it also has the benefit of generating extra starchy wort. The starch ends up being extra food for the various critters in a wild inoculation. (Remember our friendly neighborhood brewer’s yeast can usually only consume simple sugars and not the more complex carbohydrates like starches, but that doesn’t stop the other microbes from chowing down!)

In traditional lambic production, the beer is pumped out of the boil kettle into a wide, shallow tray (roughly a foot deep, maybe a bit more), which is allowed to cool overnight while exposed to the air. During this time, as the wort drops below pasteurization temperatures, dust settles onto the surface of the wort along with its attendant load of bacteria, yeast, and other microbes. Once the wort is cooled, it’s transferred into barrels for fermentation. While all the focus is usually on the magic of the coolship, there’s a fair amount of speculation that the majority of the fermenting cultures actually come from the barrels that the cooled wort ends up in. Wood, it turns out, provides a stable residence for most of our fermenting friends. (Remember, “beer history” is often just good sounding stories told by beer drinkers to other beer drinkers. Tall tales make for easy drinking.)

If you want to recreate the coolship experience, the easiest thing is just hold your wort in your boil kettle overnight exposed to the air, ideally with airflow over the top from a fan and some rough cheesecloth covering the kettle. So, finish boiling in the afternoon of your brew day, wait until the next afternoon, and run the cooled wort into your fermentors and prepare to wait. Over time, the various free-roaming microbes (known colloquially as “bugs”) that your wort collected will get down to business. Slowly, over the course of months, these bugs ferment the beer and alter its flavor characteristics. Each microbe rises to preeminence and falls away, leaving a wake of new experiences for the palate. It’s a fascinating process, fraught with nervous waiting!

Want to make your process more like the big boys? Buy stainless steel hotel pans, like the ones you’ve seen at every mediocre catered buffet meal you’ve ever had. Hotel pans are the shallow stainless steel pans designed to fit into a chafing dish or steam table to hold warm food. The standard size, at 2.5 inches deep, holds ~8.75 quarts and can be had super cheap (outside the US, this equates to the 65 mm deep, 9 L pans). Three of those and you could hold a five-gallon batch of beer overnight, easily. Just pour your cooled, inoculated wort into a fermentor and go! For the record, hotel pans come in many sizes and depths—Drew can recommend going for the slightly deeper 4-inch (100 mm) pans to simplify life.

The same rules apply for using hotel pans as for using your boil kettle. Get a (clean) fan blowing over the top to aid both in cooling and preventing flies and other animated life-forms from settling in the wort.

Getting Safer with Booze and Acid

In an ideal world, when we let our wort rest for wild inoculation it would only be visited by friendly yeasts and bacteria. You know, the things that make flavors we enjoy and love. Sadly, that’s just not the case. There are whole swaths of things longing for a wort bath that produce disagreeable flavors and worse. As Mike Tonsmeire reports in American Sour Beers, there is a chance of pathogenic enteric bacteria, like Escherichia coli (E. coli), subsisting in your wort during the first few weeks of fermentation.2 Such bacteria can also produce “undesirable metabolites such as biogenic amines” that can cause a reaction in sensitive people, not to mention causing really nasty seweresque experiences for your palate. There are other spoilage microorganisms out there with similar characteristics.

To discourage these bad bugs from attending our pool party, we need to make the scene a little less attractive. The good thing for us is that many suspect organisms are relatively weak and cannot handle a mildly acidic and alcoholic environment. This means you can get the jump on them by adding acid or alcohol to the wort yourself. For adding acid, you’ll need a way to measure pH (like a pH meter or pH strips) and some lactic acid. Drop the pH below 5 to around 4.5 with lactic acid (88%)—it doesn’t take much, a few milliliters. For extra protection, you can add some hops during the wort production.

You can add some alcohol to your wort. Choose your poison, but 325 mL of a 151 proof neutral grain spirit (e.g., Everclear®) will do the job nicely for five gallons. You want to end up at around 1% ABV; even 650 mL of standard 80 proof vodka will put you over the mark. This might seem like a lot to do for a full batch, but it gives you a safe head start. This method becomes even easier with our next approach, which is making a wild starter!

Even Safer with Wild Starters

Even with all the precautions you can take when doing wild inoculations, you just don’t know what’s going to arrive in your wort. That’s a lot of work to take a risk with, so our preferred way to do a wild inoculation for beer is to cheat and make a wild starter. Why take a chance on producing five or more gallons of drain cleaner?

The process for a wild starter is simple. Take some leftover mash runnings from a brew day (runnings in the 1.020-1.030 range) and briefly boil them to kill off any lactobacilli from the grain (you want to start clean here). Sanitize quart or half-gallon (1–2 L) sized mason jars and pour the newly boiled wort into the jars. Cover with cheesecloth that you secure with a rubber band and place the jars overnight in your target collection zone.

Once the overnight exposure is done, cover the wort jars tightly with foil and let them ferment. After a few days of fermentation, you should be able to smell and taste the new beer. Just grab a small sample with a sanitized beer thief or tube to prove your culture viability by tasting. If the taste is horribly off, throw out that starter. If you got lucky and got an interesting culture, add fresh wort to a sanitized vessel and pitch it with your new bug collection. Grow that up to at least half a gallon (~2 L) and use that starter to pitch a full batch of beer.

A few additional tips:

Another approach we’ve played with is flipping the script. Instead of inoculating the wort with stuff coming off of plants, why not add the plants directly to the wort. In particular, taking washed organic fruit (or fruit from the garden, lightly scrubbed) and putting the fruit into a starter wort works like magic. Another idea is to play around with infusions of various trees, herbs, and flowers. The same rules apply: let fermentation happen, smell and taste, and, if magic has happened, grow!

A traditional, extraordinarily cheap way to get your sour on is to pitch some grain into your fresh wort. This isn’t as far-fetched as it might seem. Barley is covered in Lactobacillus so you’re guaranteed to get sour. While cheap though, there are a lot of other critters on your grain, so we still recommend making a starter first!

The Cultured Wild

You can use cultured “wild” microbes like you can use cultured yeast. Let’s say that rolling the dice isn’t your thing and you want to get a little more science behind you. That’s fine, plenty of people are ready and waiting to help you. First, let’s go over the main microbes you to need to know about (at least, if you’re trying to perfectly recreate the main odd ducks you get in a lambic).

Lactobacillus (a.k.a. Lacto)

Lactobacillus is our fast acting, lean, mean, lactic acid-making machine. These bacteria bring the quick hit of tart, tangy acidity. We’ll talk more about Lacto shortly, but safe to say it’s an acid producer.

Saccharomyces (brewer’s yeast)

We’ve covered Saccharomyces throughout this book, especially chapter 10. It’s our good friend, brewer’s yeast.

Pediococcus (a.k.a. Pedio)

Pediococcus is one of our favorite names to say for a creature we hope to never unintentionally see in our breweries. These bacteria produce weird, deeply funky flavors, along with diacetyl (butter) and ropiness (long snotty strands of polysaccharides chained together that gave rise to calling the beer “sick”).

Brettanomyces (a.k.a. Brett)

Brettanomyces is our cleanup hitter. No seriously, in a fully wild inoculation these warriors go to town on the leftovers from the other players. Brett destroys polysaccharides and take up off-flavors. These wild yeasts make the beer well again, while also imparting a whole raft of funky, hay, barnyard, leather, pineapple, and citrus flavors and aromas.

An important note here, we tend to talk about a lot of these bugs as single species, but the reality is, like our good friend S. cerevisiae, there are countless species and strains under each genus. (OK, the exception is maybe Pediococcus, where the only one we seem to give a damn about it P. damnosus since that’s the main player in lambic.) This distinction has become more important over the years as more brewers have discovered new strains to play with.

Let’s start with the easy approach first. Get yourself a blend. These days there are so many fantastic blends available straight from talented microbiologists. Each blend will give you something different, but they’ve all been selected to be interesting and fun. Just pitch and wait for the magic to happen (give it at least six months).

If you don’t want to go the blend way, a number of brewers have been taking advantage of the advent of probiotic drinks. Taking a step back, “probiotics” is a term used to describe various microorganisms that are believed to help promote digestive health. Various pills and drinks have arrived in the grocery store proclaiming their positive impact on our guts. Probiotics are independent of traditional foods like sauerkraut and buttermilk. In fact, most take their cue from yogurt and kefir. Go pick up a bottle of GoodBelly® or a similar probiotic aid and look at the back—it will list the active cultures found in them, including numerous variants of Lactobacillus. Using probiotics is as simple as adding them to your wort. (See the “Kettle Souring” segment below for the best way to encourage sourness from these critters.)

If you want to go for the real deal and use individual pure cultures, you can do a lot with just some simple scheduling of your pitches. In Drew’s experience, which has been mostly Brett based, the prime difference is in when you pitch the Brett. If you pitch at knockout, along with or in lieu of your regular yeast, the Brett becomes very soft tasting and more subdued. If you pitch it in a secondary situation, after primary fermentation has stripped most of the sugar away, the earthy characters of Brett seem to pop more.

The Ultimate “Pure Pitch” Wild Method

(adapted from M.B. Raines, the microbiologist who taught Drew about yeast)

  1. 1. Brew the beer with a turbid mash to generate extra starch.
  2. 2. Pitch with your Saccharomyces strain and ferment as normal (2–3 weeks).
  3. 3. As the primary wraps up, add Pedio along with “food” (e.g., starter wort, fruit, etc.). The Pedio should finish in roughly 1–2 weeks.
  4. 4. When the beer smells buttery or looks ropy and “sick,” pitch the Brett and Lacto, again with a bit more food. The Brett and Lacto usually finish in roughly 1–4 months.
  5. 5. Wait for the beer to become clean again and then wait a little longer for your flavors to meld. The whole process—from mash to clean beer—should be about 8–12 months.

KETTLE SOURING: THE ULTIMATE SIMPLE SOUR

No chapter talking about simple approaches to wild beer would be complete without a discussion of kettle souring. Besides the chances of getting a bad fermentation character from wild inoculation, the main problems with wild brewing are the risk of contaminating your equipment with something undesirable in your non-funky beers and the sheer amount of time a wild ferment (even a “cultured wild” ferment) takes to produce the final product. Traditional lambics take one to three years to mature into a drinkable product and most of us don’t have the time and patience for that!

Here’s the thing though, it doesn’t take that long to produce sourness in beer. Lactobacillus, our main producer of tangy lactic acid, can drop a beer from sweet to mouth-puckeringly sour in as little as a few hours or days. It’s rather impressive.

Traditional lactic-heavy styles like Berliner weiss would be simmered instead of boiled, inoculated with a Lactobacillus culture like L. debrueckii, and allowed to sour while warm. The resulting beer after a regular fermentation was brisk and bracingly sour. Sure, a Berliner weiss lacks the deep exotic funk of a lambic, but the zippiness of the clean acid was as refreshing as a glass of cold lemonade on a warm summer’s day.

But you still have the problem of lactobacilli running around your brewery, so, just like flipping the script on wild inoculations, brewers have flipped the script on the whole souring thing. Instead of mashing, boiling, and pitching, they mash, pitch, and then boil. Because Lactobacillus works relatively quickly, you can mash and lauter into your boil kettle, then add bugs to the warm wort and let it to sit for 24–72 hours before bringing it to a boil, killing the bugs dead. Voilà, sour wort and no worries about your equipment getting infected!

Kettle souring has some disadvantages. It ties up your boil kettle and requires you to keep it warm (roughly 110°F/43°C) for the period of acid fermentation. By its quick nature, the process doesn’t build up the deep earthy funk of traditional souring methods.

The major advantage of kettle souring is it keeps fermentation equipment safe from contamination thanks to the boil killing everything off. It also has the benefit of speed of production (no more waiting months) and the focused, clean acidity that results.

Traditionalists tend to look down on the whole kettle souring notion, but as long as you know what it can and can’t do, we just consider it another tool in the brewer’s toolbox. You’ll notice this is a lot easier in many ways than the traditional methods looked at earlier.

Kettle Souring Step by Step

  1. 1. Mash your beer as normal. Raise to mash-out and lauter into your boil kettle.
  2. 2. Boil the wort for 15 minutes to kill any residual bugs from the grain. (Some treat this as an optional step.)
  3. 3. Cool the wort to 110–120°F. (43–49°C)
  4. 4. Pitch the wort with souring agents (Lactobacillus cultures, wild starters, etc.).
  5. 5. Purge the kettle with CO2. (Another step that is optional, but some believe reduced oxygen levels in the kettle results in less off-flavors; the science around this is iffy, but it makes brewers feel good.)
  6. 6. Wrap the top of the kettle with foil or plastic wrap. Wrap the kettle in insulation and hold warm for 24–72 hours with the lid on. Downward drifting temperatures are OK, just don’t let the wort get cold. If you’re using a temperature-controlled brew rig, set it to keep the wort over 100°F (38°C).

RECIPE

The Sour Cat

Catharina Sour

As we write this, Catharina sour is one of a handful of newer styles involving heavily fruited sour beers. This example from Santa Catarina, Brazil, is a stronger take on a Berliner weiss with an explosion of fresh fruits. Local favorites included strawberries, citrus, guava, and more! The key here is to follow the kettle souring procedure above and hit this with whatever fruit you want!

Batch volume: 5.5 gal. (21 L)

Original gravity: 1.045 (11.2°P)

Final gravity: 1.005 (1.3°P)

Bitterness: 5 IBU

ABV: 5.9%

Boil: 20 minutes

Malt

Mash

Hops

Yeast/Bacteria

Extras

Notes

BLENDING AND FLAVORING

One last bit of voodoo in the world of sour and funky ales. Here’s where we have to include notes from our friendly neighborhood winemakers and embrace the art of blending. Remember, we can’t depend on always getting the same flavors from our varied bugs.

The smart play when blending is to run multiple batches of beer, ferment them, and taste each batch. You’ll see that some are sourer, some earthier, some sweeter or funkier. Set up a few glasses and measure different proportions of finished beer into each to see what makes the ultimate beer. Many breweries will hold onto exceptionally sour wort in order to boost the newly fermented beer’s acidity into acceptable and pleasant realms. (Think of it like adding a splash of vinegar to a finished stew for acidity and brightness.)

What are you looking for in this mix of glasses? Let’s say you have three or four different beers. What you want to find is the proportions of beers A, B, C, and D you need to mix to achieve your “perfect” flavor. If you’re a big sour candy fan, for instance, you might aim for a very punchy, sweet-tart blend. If you’re more of an earthy funk fan, you’ll tweak the blend to be more Brett-forward with just a touch of acid to perk up the proceedings.

Regardless of what you’re going for, what you’ll discover is the blending ratio (e.g., 10% beer A, 40% B, 50% C, and 0% D) that is perfect for you. When you scale up, just blend the appropriate volumes using that ratio into one big batch and you should be groovy.

Seems intimidating? It is, but blending is a special art that offers infinite possibilities. It doesn’t just stop at different beers, you can do this same blending technique with liqueurs, wines, fruits, and other flavors as well. Play! It’s only beer!

PROFILES IN SIMPLICITY: GARRET GARFIELD

When Garrett Garfield moved to Chile, he had never brewed a batch of beer before. In fact, he drank his first beer on the way to Chile in a Canadian airport! But by the time he got to Chile, he had become a beer lover. Unfortunately, at that time in Chile there was little to no craft beer and very few good beers of any kind. So, Garret decided it was time to learn to brew his own. Like most Chilean homebrewers, he went straight to all-grain because those were the ingredients he could get. But he also did something a little different.

Garrett married a Chilean woman whose father worked at an agricultural school, where a wide variety of fruits were grown. Garret thought that would make a great place to capture wild yeast, so he set out six jars of wort (1.035-ish gravity) covered with cheesecloth in various locations around the farm. He was about 50% successful in capturing usable yeast. Garrett advises that if you try this, be prepared to toss any samples that just don’t seem “right.” After all, you don’t want to make subpar beer, so evaluate every sample carefully as to its suitability for brewing. When you have some samples that you think will be interesting, step them up to a useable pitch quantity. Interestingly, not all of the wild yeasts are funky or sour like you might expect. When Denny was in Chile, he had a chance to try several beers Garrett had made with his yeast. Some had a delightfully fruity sourness, and some were so clean that Denny thought they have been made with an American ale yeast! Not at all what he’d expected. If you’re an adventurous person, give capturing your own yeast a try.

Denny also had an opportunity to try an earlier version of the beer that’s given in the Purple Profundo recipe below. If you have access to the right kind of corn (fig. 11.1), we pretty much guarantee you that it will be a one-of-a-kind brewing experience.

Figure 11.1. Blue corn that Denny used to make chicha.

RECIPE

Purple Profundo by Garrett Garfield

Garrett plays around a lot with unique ingredients available to him in Chile, including red, blue, and purple corn. This is Garret’s spin on a modernized version of chicha, or corn beer, produced all over Central and South America. When used with certain varieties of colored corn, the beer takes on a stronger earthy flavor as well as a profound color.

Batch volume: 5.5 gal. (21 L)

Original gravity: 1.053 (13.1°P)

Final gravity: 1.007 (1.8°P)

Color: will depend on corn choice

Bitterness: 43 IBU

ABV: 5.3%

Malt/Grain

Mash

Hops

Yeast

1 Michael Tonsmeire, American Sour Beers: Innovative Techniques for Mixed Fermentations (Boulder: Brewers Publications, 2014).

2 Tonsmeire, American Sour Beers, 163.