A couple weeks ago when I announced that I will be eating only fermented food in 2014 — which I will write a book about, as an insane experiment to educate people about fermentation — one thing I promised was that I would try to learn as much as I could from the weird and wild world of food fermentation and apply it to the world of beer... and vice versa.
Well, one thing already stands out to me — in fact the first thing that truly surprised me about food fermentation. I haven't come across an exact term for this process / phenomenon, so unless someone can point the right word out, I'm calling it "self fermentation" (maybe "self inoculation" works too?) What I mean by this: in the world of food fermentation, the matter being fermented very commonly is already host to the microbes best suited to ferment it. Most foods, introduced to an anaerobic environment, will ferment themselves. The ideal bacteria best suited to those flavors and conditions are already there; the fermentation creates its own best-case scenario. It really can't get any easier.
This fascinated me when I first read about it, because it is quite foreign from how we beer brewers approach fermentation. While cleanliness is always important, sanitation with products like Star San is almost unheard of in food ferments. Is it that we brewers are extra paranoid control freaks, or is it that the world of food and booze ferments are more of a Venn diagram than a free-flowing continuum? The more I thought about the concept of self fermentation, the more it made sense. Why wouldn't the ideal bacteria already be those adapted to live on a food? Nature tends to follow a certain symmetry, and perhaps it's over-thinking our importance to assume that fermentations are meant to taste good for our benefit. We are simply reaping the spoils of a natural mini-ecosystem. An Ouroboros.
But as always, I have to come back to beer. Why doesn't beer follow this self-fermentation trend? Or, to pose a(n easily solved) riddle: can it?
The big difference between beer and other ferments is, in my opinion, complexity. And this isn't meant to sound like a beer snob putting down everything else: making beer is simply more complicated than fermenting vegetables, or even wine, mead and cider. For starters, these other fruits and vegetables can be fermented in their raw state, with very little human engineering necessary. Beer requires malting and mashing to unlock the sugars necessary for fermentation. Very few other ferments include so many factors, ingredients, and variables of process to determine the desired flavor profile. Even down to the fermentation itself: if you are fermenting vegetables, you aren't really thinking about the characteristics of the bacteria fermenting them — they're simply there, and they either do their job or they don't. Yeast seem to express a lot more versatility in their flavor profile. Therefore one strain of the generally-desirable Saccharomyces genus may create unpalatable, medicinal off flavors, while a host of others will turn out beer that is pleasantly clean and fruity, or enticingly funky and wild. When fermenting vegetables, you will end up with the right bacteria as long as you set up certain conditions for the ferment. With beer, a lack of control is more a game of chance.
So, yes, brewers are control freaks, to an extent. But this isn't a devotion to chemical-cleaning paranoia: brewers have spent thousands of years crafts hundreds of styles of beer based on the dominance of unique local strains, and now, with the ability to put those strains into vials and send them across the world, we can recreate any beer from anywhere. These strains may now be "commercial," but they were not first born in a lab — they have grown with us. The microbial landscape is a war zone (or at least a very competitive game of Risk) and we have formed alliances with a small set of Saccharomyces strains. They don't have the killswitch enzyme that their siblings in the wine world possess. They don't have the ability to drown their foes in acid, like lactobacillus. We have made a bargain with them: they will create flavors never tasted before outside of beer in return for their own exclusive playground. It is a compromise, and a small betrayal of the natives of the land. But they were all natives somewhere.
Fortunately, microbes don't hold grudges (as far as we know...), and we are able to form new alliances whenever we want, to create a totally different beer from the very same ingredients. Saccharomyces is far from the only organism to ever play a role in beer fermenations, especially if we're talking about self-fermentation. Yes, beer can self-ferment, and you've probably already solved my little riddle if you're familiar with the style of Berliner Weisse. (You should be, I just wrote about it again last week.) In fact, many old European styles rely on lactobacillus. Gose, similar to Berliner Weisse but with the addition of sea salt, is even closer to the world of food ferments. Historic farmhouse ales of Belgium and France were likely slightly sour due to the presence of lactobacillus. And that's not even getting into the rich, varied world of lambic and aged-sour beer, which relies on a slightly broader set of a organisms and a technique closer to magic than self-innoculation. (Over time, the microbes terraform the entire brewery, and brewers rely on environmental innoculation. Though one could argue that the wood in which these microbes live is itself the self-perpetuating environment... a topic for another day, perhaps.)
Sure, a lactic beer fermentation fits right in with the acidifying fermentations of vegetables and the clabbering of milk into yogurt, but there's something really awesome about a beer ferment looping back into the Ouroboros, given the added complexity of process. Barley must first be malted and mashed, and only then came fermentation begin. But the lactobacillus will return, even after the grains have been kilned, settling in and ever-ready to make the transition from solid stable food into bubbling liquid. The grains will ferment themselves... sort of. Like I said, beer is complicated. But with any food, it is incredibly interesting to view the fermentation as a magnification, a looping echo of flavors, rather than some outside alchemical magic.
Also, I call dibs on the name Ouroboros for a Berliner Weisse. My lawyers are standing by. Sorry.