Porter is a dark-coloured style of beer. The history and development of stout and porter are intertwined. The name was first used in the 18th century from its popularity with the street and river porters of London. It is generally brewed with dark malts. The name "stout" for a dark beer is believed to have come about because a strong porter may be called "Extra Porter" or "Double Porter" or "Stout Porter". The term "Stout Porter" would later be shortened to just "Stout". For example, Guinness Extra Stout was originally called "Extra Superior Porter" and was only given the name Extra Stout in 1840. However, other sources cite a reference to stout in 1677. This would provide support for the view that Henry Stout, a Quaker maltster from Hertford, England, invented stout in the 1670s.

Historically, many American breweries had a porter in their product range, including P. Ballantine & Sons (who were well known for other specialty styles as well, including a well regarded India Pale Ale and a Brown Stout). The Yuengling brewery in Pennsylvania has long had a Porter among its offerings and continues to do so today. Another well known Pennsylvania porter was Stegmaier; while the original company is defunct, the brand is still produced by the Lion Brewery. Themicrobrewery revival of the past 25 years has led to a resurgence in the popularity of the style, with many new varieties available around the world, including offerings from Deschutes Brewery,Sierra Nevada Brewing Company, Anchor Brewing Company, and many others.

History

In 1802, a writer named John Feltham wrote a version of the history of porter that has been used as the basis for most writings on the topic. However, very little of Feltham's story is backed up by contemporary evidence. His account is based upon a letter written byObadiah Poundage (who had worked for decades in the London brewing trade) in the 1760s. Unfortunately, Feltham badly misinterpreted parts of the text, mainly due to his unfamiliarity with 18th century brewing terminology. Feltham claimed that in 18th century London a popular beverage called "three threads" was made consisting of a third of a pint each of ale, beer and twopenny (the strongest beer, costing tuppence a quart). About 1730, Feltham said, a brewer called Harwood made a single beer called Entire which recreated the flavour of "three threads", and which became known as "porter".

Porter is actually mentioned as early as 1721, but no writer before Feltham says it was made to replicate "three threads". Instead, it seems to be a more-aged development of the brown beers already being made in London. Before 1700, London brewers sent out their beer very young and any aging was either performed by the publican or a dealer. Porter was the first beer to be aged at the brewery and despatched in a condition fit to be drunk immediately. It was the first beer that could be made on any large scale, and the London porter brewers, such as Whitbread, Truman, Parsons and Thrale, achieved great success financially.

Early London Porters were strong beers by modern standards. Early trials with the hydrometer in the 1770s recorded Porter as having an OG (original gravity) of 1.071° and 6.6% ABV. Increased taxation during the Napoleonic War pushed its gravity down to around 1.055°, where it remained for the rest of the 19th century. The huge popularity of the style prompted brewers to produce Porters in a wide variety of strengths. These started with Single Stout Porter at around 1.066°, Double Stout Porter (such as Guinness) at 1.072°, Triple Stout Porter at 1.078° and Imperial Stout Porter at 1.095° and more. As the 19th century progressed the Porter suffix was gradually dropped. British brewers, however, continued to use Porter as the generic term for both Porters and Stouts.

The large London Porter breweries pioneered many technological advances, such as the use of the thermometer (about 1760) and thehydrometer (1770). The use of the latter was to transform the nature of Porter. The first Porters were brewed from 100% Brown Malt. Now brewers were able to accurately measure the yield of the malt they used, and it was noticed that Brown Malt, though cheaper than Pale Malt, only produced about two thirds as much fermentable material. When the malt tax was increased to help pay for theNapoleonic War, brewers had an incentive to use less malt. Their solution was to use a proportion of Pale Malt and add colouring to obtain the expected hue. When a law was passed in 1816 allowing only malt and hops to be used in the production of beer (a sort of British Reinheitsgebot) they were left in a quandary. Their problem was solved by Wheeler's invention of the almost black patent maltin 1817. It was now possible to brew Porter from 95% Pale Malt and 5% patent malt, though most London brewers continued to use some brown malt for flavor.

Until about 1800, all London Porter was matured in large vats (often holding several hundred barrels) for between six and eighteen months before being racked into smaller casks to be delivered to pubs. It was discovered that it was unnecessary to age all Porter. A small quantity of highly aged beer (18 months or more) mixed with fresh or "mild" Porter produced a flavour similar to that of aged beer. It was a cheaper method of producing Porter, as less beer needed to be stored for long periods. The normal blend was around two parts young beer to one part old.

After 1860, as the popularity of both Porter and the aged taste began to wane, Porter was increasingly sold "mild". In the final decades of the century many breweries discontinued their Porter, though continued to brew one or two stouts. Those which did still persist with Porter brewed it weaker and with fewer hops. Between 1860 and 1914 the gravity dropped from 1.058° to 1.050° and the hopping rate from two pounds to one pound per 36 gallon barrel.

During the First World War in Britain, shortages of grain led to restrictions on the production of strong beer. Less strict rules were applied in Ireland allowing Irish brewers such as Guinness to take advantage and dominate the bottled Stout market. However, most English breweries continued to brew draught stouts until the Second World War and beyond. They were considerably weaker than the pre-war versions (down from 1.055º-1.060° to 1.040-1.042°) and around the strength that Porter had been in 1914. The drinking of Porter, with its strength slot now occupied by Single Stout, steadily declined, and production ceased around 1940. A revival of the style began in 1979 when the Penrhos microbrewery introduced a Porter. A little later, Timothy Taylor began to brew a Porter as well. There are now dozens of breweries in Britain making Porter, with Fuller's 'London Porter' winning gold and silver medals at the 1999, 2000 and 2002 International Beer & Cider Competitions, and CAMRA's Supreme Champion Winter Beer of Britain silver medal in 2007, with Wickwar Brewery's 'Station Porter' winning gold in 2008.

Today

Many breweries brew porters in wide varieties including but not limited to pumpkin,[12] honey, vanilla, chocolate and bourbon. Specialized porter brews continue the tradition of aging in barrels, and the use of bourbon barrels is not uncommon.

In addition, Okells on the Isle Of Man utilise the use of peated malt made from selected barley that uses burning peat during the malting process.

Porter in Ireland

Porter was first brewed in Ireland in 1776 as a reaction to the increasingly large imports of the beer from London. Guinness introduced theirs in 1778, and continued to brew ale as well until 1799.

In Ireland, especially Dublin, the drink was known as "plain porter" or just "plain". This is the drink referred to in the famous refrain ofFlann O'Brien's poem "The Workman's Friend": "A pint of plain is your only man." It is also mentioned in the Saw Doctors song "Hay Wrap", where the protagonist claims "I'd kill for a pint of porter". By contrast, extra-strong porter was called Stout Porter and eventually became what is today stout.

The last Guinness Irish Porter was produced in 1974, though a beer named "Plain Porter" is still brewed by the Porterhouse microbrewery in Dublin.

Stout grew into its own recognised style, however, there is still much debate today on whether this division is appropriate. Usually the deciding factor in whether a particular ale is a porter or a stout is strength. After the invention of malted barley roasted until black, also known as patent malt, in 1817, to impart a darker colour, which also gives a distinct burnt taste to the beer, Irish brewers dropped the use of brown malt, using patent malt and pale malt only, while English brewers continued using some brown malt, giving a difference in style between English and Irish porters and stouts. Stouts sometimes also use roast barley, unmalted barley roasted black, that can impart a flavour of coffee.

Porter elsewhere

Exports of Porter from Britain to the Baltic inspired brewers across the region to try making it themselves. Every country with a Baltic coastline continues to brew Porter today.

A version known as "Baltic porter" is brewed in Finland, Estonia, Latvia, Lithuania, Poland, Russia, Denmark and Sweden. It has a higher alcohol content than ordinary porters. Baltic porter was introduced from Britain in the 18th century as a top-fermenting (i.e., ale-style) beer. It remained an ale when local breweries — such as Carnegie in Sweden — began to produce it in the early 1800s. When breweries around the Baltic converted to bottom-fermentation in the second half of the 19th century, many began to brew their Porter with a lager yeast. Today only a few remain top-fermented.

In Germany, Baltic porter was brewed from the mid 19th century to German reunification. In 1990, all German breweries which produced Porter were situated in former East Germany and none of them survived the transition process to market economy. Beginning in the late 1990s, a moderate renaissance of imported porter beers in Germany led to the re-launch of Baltic porters by several German breweries. Some breweries also started to produce British-style porters. However, porter always was and still is a niche product in Germany.

Porter was initially imported to the American colonies, but by the 1700s it was being commercially brewed, especially in New England and Pennsylvania. Because of high costs of importing barley, adjuncts were often employed including sugar, molasses, corn and licorice. As a result, American porter differentiated from the English and Irish versions. Philadelphia grew into a major beer brewing center through the early 1900s. After the introduction of lagers in the United States in the 1850s, breweries began experimenting by brewing their porters with lager yeast rather than traditional ale yeast. Today, only Stegmaier and Yuengling continue to commercially produce “Pennsylvania porter” as it became known. In the 1970s and 1980s, craft brewers in the United States reintroduced American porter. Breweries such as Anchor of San Francisco and Sierra Nevada of Chico, Calif., were catalysts.