Putting the Pieces Back Together
Much of modern brewing relies upon culture yeast, purified single strains available thanks to the work of Danish scientist Emil Hansen, who propagated the first pure yeast at the Carlsberg labs in 1883 (goodbye, Brett); and on Louis Pasteur’s technique of pasteurization, which uses heat to kill bacteria in beer (goodbye, souring bacteria).
But if we step back to the days before Pasteur and Hansen, most beer must have combined—to some degree—the three elements above. Matured in wooden vessels, it was vulnerable to invasion by a range of microorganisms. Much of it must have been a little sour, and a little funky.
Yet there was good beer before the modern age of brewing: Beer was not a random, fermented slurry. Even if they didn’t know the microbiology involved, brewers learned to coax and manage fermentation and aging. They channeled the brewing process, even if they did not control it. And drinkers distinguished between sour/pleasant beer and sour/spoiled beer.
Randy Mosher, the writer and beer historian, cites old references to demonstrate that the difference. “The Egyptians had a little epithet, back 5,000 years or more, that said ‘May you have bread that doesn’t go stale and beer that doesn’t go sour,’” he says. “And if you look at English brewing books from the 18th century or so, there’s always a chapter on how to fix sour beer, even though they also valued a particular type of aged character they called ‘stale.’ That was valued, sour wasn’t. In looking back at that period, it isn’t clear exactly what they were talking about.”
Aged, or stale, beer was one of the components of porter, the style that evolved from the blended beers publicans dispensed in 18th-century London. Cheaper, fresh ale could be mixed to the drinker’s requirements with more a costly, stale beer, which no doubt exhibited a degree of bacterial sourness and some Brett. In fact, although Brettanomyces is largely associated today with Belgian brewing, it was first identified in a sample of English ale: The name means “British fungus.”
(The tradition of including a portion of aged beer in porter may—or may not—be maintained today in porter’s relative, Irish dry stout, a style that evolved from the strongest of the porters. Guinness, the most famous stout brand, has a recognizable sour note that is reputed to come from three or more percent of “vinegarized” beer from old wooden vats, blended into every fresh batch. Although Guinness does not discuss brewing details, if true, that would make this Irish dry stout the most widely consumed “sour beer” in the world.)
English porter brewers and their contemporaries appear to have perfected the controlled aging of a portion of beer in huge wooden casks, which was then blended with beers of different ages. Today, the only remnant of this technique in Britain is at the Green King Brewery at Bury St. Edmunds. Their Strong Suffolk Ale is a blend of a 12 percent alcohol, highly lactic ale matured in 100-barrel oaken vats with a younger, fresh beer.
This method is maintained today across the Channel in West Flanders, the home of sour red ale. Eugene Rodenbach, whose father founded the eponymous brewery famous for this style, studied brewing in England in the 1870s. According to Peter Bouckaert, now the brewmaster at Colorado’s New Belgium, but formerly employed at Rodenbach, “If you read what Eugene brought back to Rodenbach, it was the porter process.”
The English “porter process” may have influenced sour beer brewing in Belgium, but by the next century, Belgium would be the preserve of most, though not all, styles of deliberately soured beers.
