If you have been frequenting The Bruery’s new tasting room since it opened a few weeks ago, you may have noticed (until recently at least) a set of beers bearing the name Carmen aged with various fruits. Carmen is a dark and beautiful sour ale not entirely unlike our sour stout, Tart of Darkness.
Sour dark ales?! WTF, people who write my paycheck. WTF, indeed.
Brewing traditionalists might cry-foul at the mere notion of The Bruery mucking about in the pantheon of classic styles such as stouts, not unlike some beleaguered 10 Commandments of a forlorn and forgotten beer god who still believes in Leave It To Beaver family archetypes and pisses on the leg of anyone who uses the phrase “welcome to the 21st century”. And to those advocates of the steadfast, the tried, and the boringly true, I say: “Whatevs”.
Anywho…back to dark sour ales. Beers like Tart of Darkness and Carmen might sound strange to some, but believe me, there is some historical precedence.
Brettanomyces, the yeasts infamously found in Belgian Lambic, Farmhouse, and sour ales that produce aromas of horse blanket, smoke, and sweat…in a porter or a stout? You’re darn right.
I have an unhealthy fascination with historical beers—beers that, were it not for my propensity to piss off my wife with incessant homebrewed beer-tinkering, I might never get to try. Porter and Stout are two such historical brews that have held my carboys and kettles captive for a long time.
The history of porter and stout is the stuff of legends in the beer world, and like most legends, it holds about as much truth as a Ken Lay testimony. (Incidentally, has anyone noticed yet that my culture references are severely out of date?) Porter (and along with almost every other beer style) has had its history passed down through time in a game of academic telephone to the point that the modern version of the tale is filled with half-truths and speculation. There are a few things we can be sure of though, one of which is that Brettanomyces enjoyed porter just as much as the rest of us.
At one point in time, porter was a barreled product. And as Bruery fans probably know by now, Brettanomyces also like to go into barrels (they can live off the wood sugars). Put the two together and you get one Mutha’ Funky Porter. Read a few accounts by various brewing historians and they will all attest to the existence of Brett-based Porters. In other parts of the world, the Brett characters of clove, smoke, and horse blanket were actually considered essential components in British porter. Even a few years past World War II there was still at least one German brewer who used Brett in his “British Porter,” claiming that it was absolutely necessary to get the style right.
Modern accounts can make for some confusing reading, however. Some describe historical porter as tart and acidic from the use of Brettanomyces yeasts. While I’m sure that Brett just dove right into the beer and made a lovely home for its brood of bizarre flavors and aromas, it is not a yeast that will produce appreciable acidity in beer. (It can make a beer VERY dry by eating all the sugars that regular brewer’s yeasts think they’re too good for, and this dryness can sometimes be mistaken for acidity, however to most people the two perceptions are very different.) Brett will produce a fair amount of acetic acid (the acid in vinegar) if the conditions are just right (properly cellared barreled beer ain’t it though), but tartness and acidity in beer are usually associated with lactic acid production, something that Brett doesn’t do very well. Bacteria like Pediococcus and Lactobacillus do make a lot of lactic acid, which is why they are collectively and mundanely referred to as Lactic Acid Bacteria. So if some of these accounts are to be believed then it’s likely that producing a traditional porter would require pitching in some of these guys as well.
Really, I can only support my theory by extrapolating from statements like those above, though it would make sense that Brett wasn’t the only thing influencing historical porters in the barrel. (By the way, esteemed beer blogger Martyn Cornell has offered some interesting notes on historical porter flavor worth reading, here.) A lot of microbes can hang out in barrels, lactic acid bacteria being among them. Part of my graduate research was based on complaints from winemakers that whenever they found Brettanomyces in a barrel they often found Pediococcus as well. Lactic acid production by these bacteria is fairly strain-dependent, with some producing enough make your mouth cave in and others spitting out only tiny amounts. So it’s likely that you would have found some porters that were not as sour as others, potentially explaining the discrepancies of reputed sour levels. Also, some strains of Lactobacillus, though rare, can produce phenolic compounds similar to Brett yeasts.
So what am I saying here? While it’s probably not possible for us to ever know for sure, I think the argument can be made that early barreled porters had a fair amount in common with American sour beers or even Belgian Lambic, at least spiritually. It’s fascinating to think about what these historical beers actually tasted like. It also makes me wonder about other brews back in the 18th and 19th centuries. A lot of beers were barreled for shipping purposes or just to condition for a while. If Brett was a major part of Porter all those years ago, is it not possible that perhaps the famously barreled English IPA was also a Brett bomb, or that some of them may have even had some acidity? (The hops in IPA’s are usually pretty good deterrents against lactic acid bacteria, though a lot of strains do have resistance to them.) I’ve never seen reference in the beer history books about IPA’s referred to as “barnyardy” or “tart,” but who knows? Maybe the game of beer history telephone has obscured more of brewing’s oh so funky past. In any case, here at The Bruery we’re going to keep on keepin’ on, experimenting with styles and bending the rules. But in the case of Tart of Darkness and Carmen, I think that in a way we’re just following in the footsteps of all the famous beer-benders of brewing’s past.