You’ve no doubt seen a distinction in beer between stouts and porter styles, whether at a grocery store or a brewery. Although these words might indicate a distinction today, their historical characteristics are not the same. In fact, the entire style – even in its birthplace of England – has changed drastically.
The story begins during the mid-1600s, when the working-class population experienced a series of hardships, including a plague and being forced off their land. This left a large number of people without work and homes, so they flocked to cities to find both. When London and other cities began experiencing economic growth, these people were the backbone supporting this boom.
In London, a new, cheap brown malt became the standard for brewers around the city. At that time, recipes weren’t changed to create different styles and beers, but rather, brewers used one recipe and aged their beers for different lengths of time. Older beer took on a sourish taste and was called “stale beer” – which was not meant to indicate a fault. Fresh beer, in contrast, was called “running beer.”
Also contrary to today’s methods, these different brews were not ordered and consumed as different styles, but instead, they were blended according to patrons’ wishes. Eventually, as some stories and theories claim, a “master blend” was created, which became the standard drink. The primary consumers of this master blend and the blends before them belonged to the lower class – people who generally worked at the ports – and so the style was named.
The economic boom continued and became the Industrial Revolution during the mid-1700s. Raw materials became more accessible, which increased brewing capabilities. In fact, brewing was one of the first industries to become industrialized on a large scale.
This boom in beer lasted into the first couple of decades of the 1800s, but as we know, industrialization is not kind to beer. As larger-scale brewing was required, brewers cut corners and made changes in the name of efficiency and profitability. As you can guess, the complexity of the porter disappeared, and a different sort of dark-brown brew replaced it.
Around 1725, the word “stout” began to be used to denote any beer – not just dark beer – that had a higher alcohol content than standard pub levels. But, because of porter’s popularity throughout Europe, the term began to be used with strong versions of the style almost exclusively as “stout porter.” By the early 1800s, it became known simply as stout, and the practice of using it to denote a higher alcohol content was all but forgotten.
Like most styles when they’re created by American brewers, stouts and porters were made more alcoholic and with more hops than their European versions. These were no longer beverages for the working class – they were big, flavorful, dark brews revolutionized by American craft brewers. They were more on par with foreign-export stout levels.
Over the years, even the definition of an American stout or porter evolved and became more of a loose term for brewers to play with.
Historically, the distinction between a stout and a porter is simply a matter of alcohol content. This can still be true in some cases, but my fellow dark-beer drinkers have either made their own distinction or simply ignore the words, as I frequently do.
The American porter is generally less assertive than American stouts. Although both can have some burnt or roasted characteristics, stouts generally have a higher level of those, while porters have richer, sweeter caramel and chocolate notes. American stouts have a higher bitterness level (IBU), alcohol content (ABV) and darker color (SRM), but the styles overlap heavily on all fronts.
Although history created a distinction between stouts and porters, modern versions do not differ greatly, and rarely in ways that matter to a beer drinker. If you’re interested in brewing, the differences may be more important, but with all the wild ingredients that are added to today’s brews, I recommend not dwelling on the differences and taking a chance on these dark beauties as being almost interchangeable.