Irish Stout traces its heritage back to Porter. As described previously in our article on the Porter Beer style, Porters were first commercially sold in the early 1730s in London and became popular in both Great Britain and Ireland.
The word Stout was first associated with beer in a 1677 manuscript, with a “stout” beer being synonymous with “strong” beer (Ref:Wikipedia). In the 1700′s the term “Stout Porter” was widely used to refer to a strong version of Porter. The famous Guinness brewery in Ireland started brewing “Stout Porter” in 1820, though they previously brewed both ales and Porters. Around 1820, Stout also began to emerge as a distinctive style, using more dark brown malt and additional hops over popular porters of the time. At around the same time, black malt was invented and put to good use in Porters and Stout Porters. (Ref: Daniels)
Throughout the 1800′s Stout continued to refer to “Strong” – therefore one could have “Stout Ales” as well as “Stout Porters”. However, by the end of the 19th century, “stout” became more closely associated only with dark Porter, eventually becoming a name for very dark beers.
Traditional stouts of the 1800′s and early 1900′s differ considerably from their modern counterparts. The characteristic Roast Barley that gives Irish stout its dry roasted taste was not widely used until the early to mid 1900′s. Some Stouts had very high gravities – 1.070 to 1.090 for many recipes from 1858 cited by Ray Daniels. They also had very high hop rates, in some cases approaching 90 IBUs.
As Pale ales and later European lagers became more popular in the 1800′s, sales of both Porter and Stout Porter declined, remaining popular in Ireland and a few other localities in the UK.
The definitive modern Irish Stout is Guinness Extra Stout. Other popular commercial stouts include Beamish Irish Stout and Murphy’s Irish Stout. Founded in 1759, Guinness brewery at St James gate in Dublin Ireland has operated continuously for over 250 years under family ownership. Guinness is a classic Irish or Dry Stout style, with a distinctive dry, almost coffee like flavor derived from Roasted Barley. Guinness is brewed in two main forms, the domestic draft version having much lower alcohol content (3.9%) than the export bottled version (6%). (Ref: Daniels)
A number of other stout styles are popular including (Russian) Imperial Stout, Oatmeal Stout, Milk Stout, Chocolate Stout. However for today, we will stick with the classic Irish Stout style.
Designing and Brewing an Irish Stout
I rish Stout has an original gravity in the 1.035-1.050 range, with domestic versions being at the low end and export versions at the high end of that range. Bitterness is moderate, but must balance the strong flavor of the dark grains used. It should be hopped at a moderate rate of 1 IBU per point of OG (so a beer with 1.040 OG should have 40 IBUs). Color is an extremely dark brown that looks black in the glass – from 35-200 SRM. Traditionally Irish Stout is served at very low carbonation (1.6-2.0 volumes) and often served warm.
The key ingredient in a classic Irish Stout is Roasted Barley. Roast Barley gives Irish Stout its classic dry coffee-like flavor, deep dark color, and white foamy head. Unlike other dark malts, Roast Barley is made from unmalted barley grain that is roasted at high temperature while being lightly sprayed with water to prevent it from burning. Roast Barley is intensely dark, around 500-550 L, but amazingly the unmalted barley produces a white head on the beer as opposed to the darker head made by other malts.
In many commercial dry stouts, Roast Barley is the only specialty grain used. For a Dry Irish Stout, Roast Barley makes up around 10% of the grain bill. Those that don’t use Roast Barley will almost always used Black malt as a substitute.
Irish Stout is famously full bodied, so the second most popular ingredient is a specialty grain to enhance the body of the beer. Guinness uses Flaked Barley at a proportion of around 10% of the grain bill. Flaked Barley adds significant body and mouthfeel to the beer, but it must be mashed. If you are a malt extract brewer, crystal malt or Carapils would be a good substitute for Flaked Barley.
Many award winning all grain stout recipies also use oatmeal (6% of grain bill range) or wheat (6% range) either in place of flaked barley or as an addition to further enhance the body of the finished beer. Other popular specialty grains include black and chocolate malts, though these are used in small proportions primarily to add complexity to the flavor. (Ref: Daniels)
English pale malt (or Pale Malt Extract) makes up the bulk (60-70%) of the grain bill. For all-grain brewers, a medium to full bodied mash profile is desirable. Asingle step infusion mash is sufficient for well modified English malts. Conversion mash temperatures in the 153-156 F range are appropriate.
The most popular Irish Stout hops by far is East Kent Goldings, though other English hops such as Fuggle, Challenger, Northdown and Target. American varieties such as Cascade are sometimes used by American microbreweries. Traditionally a single hop addition is made at the beginning of the boil for bitterness. Hop aroma is not a significant factor, so aroma hops are rarely added to Irish Stout.
Irish Ale yeast is traditionally used in Irish Stout. An ideal yeast would yield an attenuation around 76% for dryness, but many Irish ale yeasts yield a lower attenuation. Some brewers select neutral yeasts with a higher attenuation to achieve a drier flavor profile. London and Whitbread yeasts are also popular choices.
Some Irish Stout recipes, including Guinness use a small amount of soured beer to add a little extra bite and flavor. To make soured beer, pull a small amount from the unfermented wort and let it naturally sour over several days by leaving it exposed to air. Boil the sour beer sterilize it thoroughly and then cool it and add it to your fermenter well before bottling.
Finally, few stout fans will forget the smooth creamy head that a draft pint of Guinness has on it. The secret is that Guinness on tap is not served under CO2 alone, but has a mix of CO2 and nitrogen. The nitrogen gives it the extra creamy long lasting head. You can serve kegged beer with nitrogen and CO2 at home, but it requires a separate tank of nitrogen in addition to a tank of CO2 and also a special “stout tap” to mix the gas when serving.
Irish Stout Recipes
Here are some sample recipes of Irish Stouts, as well as a few other Stout styles thrown in for variety:
All Grain Irish Stout Recipes:
Extract Irish Stout Recipes: