That picture shows how I knew it was working: a bit of brown liquid had blown through the rubber gasket on the swing-top. At the height of activity, the bottle was hissing like an asthmatic cat, releasing built-up carbon dioxide as the yeast did its work. It meant that my first experiment in beer hacking was successful, at least as a proof-of-concept. What remained to be seen was how it would taste.

What I started with was originally straight Pardubický Porter, a Baltic Porter from the Pernštejn brewery here in the Czech Republic. I liked the beer plenty, but sometimes I thought it was too sweet. And I wondered if I could change it using a minimal amount of effort. In particular, I wondered what it would taste like if it was inoculated with brettanomyces. So I filled a couple of swing-top bottles with draft Pardubický Porter and dosed them with the dregs from a bottle of Orval, which I knew should contain some brettanomyces.

I called it “beer hacking,” meaning “modifying a commercial beer to suit your own tastes.” The idea got some attention. Jeff Bell commented that he didn’t think it would end well. William Brand wrote in to note that Orval actually has two yeasts in each bottle, so I’d be getting regular ale yeast as well as brett. And some dudes on Reditt started debating if it would work or not.

Oh yeah. It worked.

My original thought was that the yeast in the Orval bottle might be dead, so all I would end up with would be the effects of autolysis. But when I found the bottle spitting and wheezing in the beer room, I knew there was enough life for the beer to undergo a secondary fermentation. I let it sit upright at winter room temperature for five months, and then opened it at the end of a recent kitchen table tasting.

It spewed like Champagne.

Once the gushing stopped, we poured four good glasses. Instead of coffee and cocoa sweetness, the nose had loads of horse-blanket and barnyard aromas. There was a tack-like leatheriness in the mouth, with a lovely tannic structure. It was sour — not lambic sour, but sour-sweet like a Flemish red. And the mouthfeel was quite different for me: the hacked beer gave the impression of being more substantial, vinous and heavy in the mouth.

If you put it in stemware and gave it to an unknowing guest, he’d probably ask what kind of wine it was.

I’ve still got one bottle left, which I’ll try again in a few months. And another project with a different beer — a simple hack of a standard Czech pale lager — is currently underway in the refrigerator right now, which I’ll report on in a few weeks. I still plan to age Pardubický Porter in an oak barrel someday, or at least put it on oak chips. The possibilities for beer hacking are endless.

Of course hacking a beer is not the same as brewing one. But at least it’s slightly more involved than the basic, open-bottle-pour-in-face type of beer consumption. Not every experiment in beer hacking is going to land butter-side-up: my attempt to make an Eisbock last month resulted in two very flat, very unfrozen, very ruined half-liters of Czech strong lager. But it is all in the name of science.

Our thoughts are with Bill Brand. We’re raising a glass of hacked beer to him tonight.

Call it an auspicious start to 2009 for lovers of good beer: in the very center of Prague, a major Czech supermarket now has a large selection of great Trappist ales at the best prices in town.

Most of these beers are available elsewhere in Prague, so don’t expect to find any unknown gems among the supermarket’s Budvar and Pilsner Urquell bottles. As I wrote in a post that was lost in the Wormhole Incident™, you can find well-known Belgians at Pivovarský klub and Pivní galerie, though you’ll burn through your pocketbook if you do, as prices for a small bottle of the globally ubiquitous Chimay can hit 153 Kč ($7.90 / €5.70).

In my earlier post, I forwarded a friend’s recommendation for the cheese shop Cheesy, with branches around Prague and around the country, and where most of the Trappist ales list for 75 Kč or so per 33-centiliter bottle. (An exception was the legendary Rochefort 10, which cost 90 Kč.)

But the prices at the Billa supermarket are even better, and with a more central location. Right at Náměstí Republiky, the Billa on V celnici street charges 63 Kč ($3.25 / €2.35) for a small bottle of Orval, the best price I’ve heard of for what can be one of the very best beers in the world.

Rochefort 6 and 8 are also 63 Kč; Rochefort 10 is 80 Kč. Small bottles of La Trappe and Westmalle start at 60 Kč. Most of the fruit-lambic lineup from Lindemans is available at similar prices (although I didn’t see Cuvée René, the brewery’s better old gueuze).

The best news, however, is that Billa also carries the large, .75-liter bottles which are perfect for aging. Corked-and-caged wine bottles of Chimay Cinq Cents, Grande Réserve and Première are all just 160 Kč; the wonderfully complex Achel Extra Bruin boasting 9.5% alcohol is just 200 Kč; big bottles of Westmalle Tripel are 180 Kč.

Why does this matter? Because Czech beer culture’s tough bounce is the extremely high price of foreign beers: even at 63 Kč for an Orval, you’re paying three times the cost of a Pilsner Urquell or Primátor Stout. Such prices mean foreign brews remain out of bounds for most people, which in turn means that regular Honzas and Hankas here have no experience with even the most mundane beer styles from abroad. (Let’s be honest: we’re not talking about truly obscure beers here. These are Belgium’s usual suspects.) In turn, this means that people continue to drink one style of beer, pale lager, which constitutes 95% of Czech consumption. In general, such homogeneity is not a hallmark of a healthy beer culture.

But beyond merely having lower prices, the arrival of Belgium’s usual suspects at Billa means something is changing. Before, these beers were only available in a couple of beer shops in town. Later, you could find them in a few specialty food stores. Now, in addition to lower prices, we’re seeing the progress to mass distribution of quality foreign beers in a place where thousands of Praguers buy their daily groceries.

Instead of Belgium’s best-known brews, I’m sure that Velký Al would prefer to see more real ale from the UK. I’d bet that Pivní Filosof would rather see more Czech regional microbrews. And I’d agree with both of them. But one thing at a time. 2009 is already off to a very good start.