Irish Stout (15b)

Purpose: Create an Irish Stout (15b) recipe

1. Enter the batch target values

original specific gravity (1.036 to 1.044)
% mash efficiency
volume (include wort losses)
US (gallons) Metric (liters)

2. Select the base malt

@ SG
@ SG
@ SG
@ SG

3. Enter the specialty malt percentages

Essential - Roasted barley from 5% to 12%:
% @ SG

Commonly used specialty malts (5 to 25%):
% @ SG

Variations on roasted character (5% or less):
% @ SG
% @ SG

Other possibilities:
% @ SG
% @ SG

Optional sugars for lighter body (5 to 20%):
% @ SG
% @ SG

4. Enter the target IBUs and bittering hops

total IBUs (25 to 45 recommended)

Hop addition #1: minutes bittering hops boil time

@ AA%
@ AA%
@ AA%
@ AA%
@ AA%

5. Late hop additions

Irish stouts typically lack hop aroma and flavor.

number of late hop additions

6. Select the yeast type


← Click here when the data entry is done.

Results: *** Waiting for results ***


The primary character of contemporary stouts is from roasted barley, with the typical amount being 5 to 9% by gravity points. (By weight, a common figure is roasted barley is 10% of the grain bill weight.) Most Guinness stout clones from BYO magazine use an average of 8% roasted barley (range: 5 to 13.5%). Other roasted malts, such as chocolate malt or black patent malt, can also be used for roasted character.

Another commonly used ingredient is flaked barley, with an average of 15.5% (range: 5 to 27%) from the reviewed recipes. Some experts say that flaked barley is optional, but beer judges in homebrew competitions seem to expect the presence of flaked barley. Crystal malt or wheat malt are occasionally used in this style. Keep these to a minimum. The base malt is ideally a British-type pale ale malt.

British hops like Kent Goldings, Fuggle, and Target are recommended. Neutral bittering hops will also work. Estimates of the IBUs in Guinness range from 35 to 45. Most stouts do not have a significant degree of hop flavor or aroma. Accordingly, a single hop addition for bittering is typical, although a few recipes have a 15 minute addition (<=5 IBU) at the end of the boil.

The most authentic yeast would be Irish ale. Neutral American yeasts and British ale yeasts that attenuate well are good alternatives.

An important challenge for this beer style is getting a low final gravity (1.007 to 1.011). Step mashing or single step mashes at lower mash temperatures (148F) may yield a more fermentable wort. Using some sugar in place of malt can also help to lower the final gravity.

A second challenge is that roasted barley is acidic, which could potentially lead to a mash pH that is too low. The brewing water may need to be slightly alkaline to counteract the acidity.


Colby, C. (2011, January-February). Delicious dry stout. BYO, 40-49.

BYO Staff. (2005, June/July), Guinness draught clone. BYO.

Kaiser, D. (1998, December). Irish stout. BYO.

Zainasheff, J. (2008; September). Dry stout: Dark, roasty, and easy-drinking. BYO, 19-23.

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