This post could very well be a story: The tale of two beers closely linked in origin, born in the pubs of London, weaving a path through the industrial revolution, weathering the inter-war years and emerging as unique and diverse styles upon the wave of the craft-beer revolution. While the history behind the origins of porter and stout is certainly intriguing, it is not my mission (nor is it within the reasonable scope of this post) to thoroughly investigate the past of these two beers. Rather, I am interested in the practical differences between stout and porter; differences that you (the beer consuming public) should know the next time you enter a store or bar.

The Beginning

While a thorough history lesson is out of the question, any discussion of the relationship between these two styles would be incomplete without a brief trip to the past. Porter was born in the 18th century pubs of London, a blend of younger pale ales and darker older ales that resulted in a full flavored and hearty pint favored by the porters of the city. While the specific composition, name and originator of this blend is a disputed topic, the growth of the porter style outside of the pub is not.

London’s breweries began producing a beer intended to mimic the popular pub creation on an industrial scale. These porters were produced to varying strengths, with stronger fuller bodied porters being labeled "stout porter." Eventually, porter was dropped from the label and stout, as a distinct style, was born.

Stout and Porter Today

Modern brewing practice entails one (albeit fuzzy) distinction between stout and porter. Stout is brewed with roasted barley; porter is not (or less commonly). Roasted barley is un-malted and has been roasted at a high temperature to a blackened state. It imparts a range of roasted aromas (think coffee and dark-chocolate) to beer as well as a dry bitterness on the palate (as opposed to the resinous bitterness imparted by hops).

The use of roasted barley means stouts, broadly speaking, have more pronounced and deeper roasted notes to the nose, as well as a more pronounced dry bitterness on the palate. Porters are commonly perceived as sweeter on the nose and palate. Furthermore, the color range for stouts is darker, ranging from dark brown to black, while porters rest more firmly in the brown spectrum.

The Fuzzy Part

The economist in me wishes I could assume the rest of this article out of the model. The thorough journalist in me, however, is thrilled by the opportunity to untangle the more nuanced reality of the relationship between stout and porter. While stouts almost universally employ the use of roasted barley (there is only one exception I can think of), roasted barley also makes its way into a number of porters. The simple distinction between stouts and porters is further complicated by the extreme diversity within the stout and porter categories.

A Range of Styles

Stouts range from dry to sweet, from low in alcohol to high. They contain a wide range of specialty ingredients, from oatmeal, to chocolate, to peanut butter (see Short's). Porters also manifest in numerous forms, from relatively mild to strong, from rather standard production to smoked and barrel aged beers. This diversity makes any simple distinction between the two styles almost irrelevant. The following is a brief summary (look to a future post for a more exhaustive investigation of stouts) of the styles of stout and porter:

Dry Stout: The style name says it all: roasted coffee on the nose with a pronounced dry bitterness on the palate. The most common expression of this style is Guinness Draught. Skip the Guinness and grab a locally made Dry Stout on tap at Arbor Brewing Company (Fancy Fest Irish Stout) or Grizzly Peak (County Cork's Irish Stout).

Sweet Stout: Again, it's all in the name. These are considerably sweeter than dry stout; they're sometimes referred to as milk or lacto stout, from the use of lactose sugar to sweeten the beer (lactose is un-fermentable and thus carried through as residual sugar in the final product). The classic example would be Mackeson's XXX (no longer available). However budget-conscious beer consumers can find a sweet stout in Sam Adams Cream Stout (my favorite value beer of any style).

Export Stout: Dry or sweet stout brewed to a higher strength (more bitterness and alcohol) to increase stability for export. More pronounced roasted notes on the nose but more importantly, fuller flavor on the palate. Guinness Export Stout is the standard for the style and considerably more tasty than the draught version.

Oatmeal Stout: Stout brewed with oatmeal. Oatmeal lends a smooth quality to the palate. New Holland's The Poet holds a special place in my heart as one of the first beers I can remember truly appreciating.

Russian Imperial Stout: A style born to withstand the long journey from England to Russia. It is brewed to a much higher alcohol by volume and with considerably more hop bitterness. Founder's Imperial Stout is my current favorite.

London Porter: Classic interpretation of the style. Sweeter roasted notes on the nose than found in most stout, it is also usually less dry on the palate. My favorite is Arcadia's London Porter, which is wonderfully rich with a subtle smokiness to the nose. Arcadia crafts their porter with a bit of smoked malt, hearkening back to the wood fire kilned malt used by London's original porter breweries.

American Porter: Like most American takes on British styles, the defining quality of these beers is a higher level of hop bitterness. The standard for me is Sierra Nevada's Porter, an easy drinking porter with noticeable west coast hop aroma. It's the perfect beer when I am in the mood for something darker but still easy drinking. For a local fix, grab a six pack of Founder's Porter (Kentucky Breakfast Stout Light).

Baltic Porter: Porters brewed in Northern Europe, originating from stronger porters shipped from England. It's not only higher in alcohol but also tends to be a bit sweeter. The standard is Okocim Porter from Poland which has sweet chocolate and plum notes to the nose and is syrupy sweet on the palate. For a more interesting take on the style search for some Arcadia's Shipwreck Porter. This beer is aged in whiskey barrels for ten months, and it shows through a pronounced vanilla/oaky quality on the nose.

Note on references: This post would not have been possible without Ray Daniel's book Designing Great Beers

Ryan Sloan is an employee at Morgan and York, musician and beer-writer. He maintains a personal blog and can be reached at rysloan4@gmail.