by Richard B. Webb

The origins of the beer style known as Porter are lost in the pre-history of brewing. Not only were modern brewing techniques unknown, but there were no standardized brewing instruments for measuring such things as specific gravity or temperature. Record keeping was spotty at best, and each brewer was loathe to give up precious secrets to a potential competitor. Thus most of what we know about Porter is conjecture and guesswork at best, and possibly flat out wrong at worst.

Traditionally, Porter is thought to have been created from three distinct mashings. The first mash was held at 150 degrees for one hour. The grains were then drained, and a second mash was then held at 160 degrees for 1/2 hour. The grains were then drained, and a third mash was then held at 180 degrees for 1.5 hours. These three run offs were then combined and boiled for perhaps three to four hours.

The hopping rate of the ancient Porters is also not well known. The hops that are used now were unknown then, and the hops in use then are not used now. Forget about asking what the alpha acid content of these hops might have been. The oldest of the hop types now used is the Goldings, first cultivated in the 1780's. This could have been used to make Porter, but probably wasn't! Goldings are considered to be the classic pale ale hop, and the makers of Porter were conscientiously trying to make something that was NOT a pale ale! One can assume that the hop acid content of the hops used in Porter were perhaps the equivalent of the Golding, at around four to five percent alpha acid.

Scant records exist as to the amount of hops to be used, but Terry Foster, from whose book most of this treatise is distilled (some would say stolen), imagines that the hopping rate as expressed in these old records indicates a level in excess of 60 IBU, a healthy hopping rate indeed.

Who knows what kind of yeast was used in this old, original Porter? In fact, the style of Porter had been around for 150 years before yeast was even discovered as the driving ingredient of fermentation. Most likely, the yeast was the same top fermenting yeast as was used in the brewing of Pale ales.

Porter was also known as a beer that required long storage. This storage could last perhaps an entire year, and when the technology had evolved sufficiently, large quantities of Porter could be stored in large wooden vats for a long period of time.

Economics also was a driving force behind the style that was Porter. The price of beer was not determined by the price of ingredients, or the price of doing business. Instead, the price was dictated by English law, allowing the ingenious brewer to make the maximum profit from the cheapest of ingredients. The brown malt used was considered ideal, not because of maximum extract, or from any character imparted to the brew, but instead because it was the cheapest malt to be found.

To summarize, the original style of Porter has the following characteristics:

• Made from a highly dried but not roasted brown malt
  
  
• Original gravity from 1.060 to 1.070
  
  
• Three separate mashes, all runnings collected together
  
  
• Color a deep red-brown, perhaps with a color of around 25-35 degrees L
  
  
• High hop rates, with perhaps 4 ounces of four to five percent acid hops added the beginning of the boil, with no later hop additions
  
  
• Fermentations at ambient temperature
  
  
• Top fermenting yeast with a 75% attenuation, resulting in high alcohol, and with residual sugar
  
  
• Low carbonation levels, as the open kegs in the publicans house would release any buildup of CO2.
  
  
• Long storage in wooden vats, possibly contaminated with acid producing bacteria

The pinnacle of Porter brewing probably occurred in the early 1830s. After that, the amount of Porter actually brewed in London began a long, slow decline. However, the making of Porter spread to all points of the globe, following the soldiers and bureaucrats of Britain all across the Empire. Today there are distinctive Porters being made in such unlikely spots as Jamaica and Thailand, but these far flung breweries would be making a Porter as much unlike the original as can be imagined. Porter has been brewed for so long, by so many brewers, that the modern interpretations probably bear little resemblance to the original dark knock off beer of some grimy back street brewery using contaminated well water from the East side of London. Modern Porters tend to have the following characteristics:

• Original gravity of 1.045 to 1.060
  
  
• Final gravity of 1.010 to 1.015
  
  
• Color from 35 to 70 degrees L
  
  
• 25 to 45 IBU
  
  
• Alcohol around 3.6 to 4.8 % by weight

This modern definition of Porter leaves a lot of leeway for characteristics such as gravity and color. In fact, this list sounds similar to an equivalent list such as one might make for pale ale. Thus we can imagine that it is the color adding darker, roasted malts which transforms pale ale into Porter in the modern interpretations.

Modern Porter should be full bodied, having a strong malty flavor from the roasted and dark caramel malts used in its manufacture. A higher than expected alcohol level is required for the warmth and alcohol balance required of beers that are meant to be stored for long periods. The high attenuation leads to dry, not sweet tasting beer. Porter should have a estery character, and a burnt, coffee-like taste from roasted malt, topped off by a definite hop bitterness, with a lot of body. And all of these flavors should be in "balance." (If you want to get into a fight with a brewer, ask them how they feel about "balance.") Perhaps for our case, balance can be described as all flavors in harmony, without any one taste overpowering any other taste. However, if one can achieve a pronounced hop bitterness, as well as a strong roast malt flavor, then you have made a Dry Stout, and not a Porter at all! In fact, AHA Porter definitions now contain distinct Porter styles, with "Robust" Porter, having an accent on black malt flavor with no roast barley, and "Brown" Porter, having no roast barley OR strong burnt malt character.

This page is authored and maintained by Rich Webb.You can send E-mail to me by following this link to the contact page. And feel free to contact me if you have any comments, criticisms, or suggestions. I remain, however, perfectly capable of ignoring your useless opinion...

This document was properly placed here on Dec 20, 1996, and has been viewed countless times. In fact, it appears to be one of the first pages I ever put up on the web. Information is Power...