Are stout and porter two beers or one? How do brewers, and drinkers, differentiate the two styles and is there a meaningful difference? To answer these questions we need to look back into brewing history and see which ale came first, and how both styles developed.

The history of porter

Let’s start with London brewing in the early 1700s. Before this time, brewers dispatched young beers to the pubs, where publicans aged them to their own preference. This way came under pressure in the capital from the growing popularity of brown ales — lightly hopped beers made with brown malt aged before sending out.

The quality of brown ales was higher, and more consistent (thanks to improved brewing methods), and drinkers quickly switched. The response was to take on brown ale at its own game, producing something stronger (around 6.6% ABV) with more robust flavours.

Stronger brown ales quickly became popular with workers tasked with carrying goods around London. This was heavy, thirsty work, and they desired a drink full of rich carbs and character. The workers were called ‘porters’ and this quickly became the name of the ale.

Where does stout enter the story?

With the name porter firmly attached to the ale, by the end of the 18^th^ Century improved distribution (via railways and boats) meant London porter could push out into the regions, and across the Irish Sea.

Alongside this, brewers made porters at varying strengths, reflecting personal taste amongst drinkers. Wherever english-style strong ales were made the nomenclature ‘stout’ was added to the name; leading to the name ‘stout porter’.

The popularity of porter repeated itself everywhere, causing problems for local brewers. In Dublin the St. James's Gate Brewery, owned by a certain Arthur Guinness, retaliated by making its own version. Production started in the 1780s with a strong porter; reflecting Irish preference (remembering porter itself is a stronger form of brown ale). With ‘stout porter’ already being an accepted term, St. James’s Gate Brewery chose the name ’Guinness Stout Porter’ for their ale.

Debates are everlasting over differences between porter and stout (which we’ll get into below) but at the base of it all is the simple fact of both drinks being the same thing, with stout having a higher ABV.

Porters fall, stouts rise

The 1860s saw a decline in porter’s fortunes. Pale ales (like IPAs and bitters) were on the up and brewers who persevered with darker brews lowed the ABV, making ‘mild porters’. Then came the First World War and restrictions on the use of grain for beer making. These limitations further lowered the ABV, and quality, of dark beers but porter struggled on till post-World War II with brewers finally giving up in the 1950s and ceasing production.

That was the story in London, and across the mainland. Ireland (before independence) and Éire (post independence) didn’t have the same wartime restrictions and ‘stout porters’ thrived thanks to Guinness, Murphy’s, and Beamish, with the ale’s name now shortened to simply ‘stout’ by the time it was reintroduced to the mainland.

Stout and porter --- Taste the difference

Brewing methods have changed much since the 1700s and whilst stout and porters are historically the same drink that doesn’t mean there aren’t some variations between modern incarnations. One common distinction is the use of barley. Porters use malted barley and stouts unmalted roasted barley.

This gives stouts a stronger coffee aroma, the first characteristic used to identify one from the other. In fact, this is probably the strongest distinction between them, the others being so slight as to be undetectable to many. Consider this list:

  • Stouts and porters are both decidedly dark, stouts edge more towards black.
  • Porters have almost no hop aroma, stouts may have a little.
  • Porters tend to have a creamier mouthfeel.
  • Porters taste slightly more acidic than most stouts.
  • Stouts underscore coffee aromas.

With such paper-thin separation between the drinks we’d suggest focussing less on deciding if you prefer stout or porter and instead focus on enjoying both, and making a choice between individual brewer’s styles.