Breaking down the broad stout style group into its individual substyles can be a bit difficult. Think of stouts as blondes–it’s in the contrast, you see. You have Catherine Deneuve (French) blondes, Claudia Schieffer (German) blondes, Pamela Anderson (Canadian) blondes, Christine Applegate as Kelly Bundy (American) blondes, Anna Kournakova (Russian) blondes, and A. A. Gill’s The Blonde (English). All are female, blonde, sexy, desirable, but each is different: sultry French, stunning German, wild Canadian, dumb but luscious American, she of the skimpy tennis outfits Russian, and stunning English. There–a sixer of blondes, sufficient for all but the lustiest.
Some British brewers use aggressive American hops to great effect in some of their beers, but the results are un-British.
To female readers: I have no idea what turns women’s heads, so feel free to substitute male names at will. [Hmmm...Mel Gibson, Denziel Washington, Gabriel Byrne, Ralph Fiennes, Christopher Lambert, Mikhail Baryshnikov--Ed.]
The Three Oat-Based Stout Substyles
Within the stout group of ales, there are many substyles. Stouts made using oats–in different forms such as flaked, pinhead, rolled, or malted–in the recipe are substyles of the group. The sharp-eyed reader has already noted that I use the plural. That is because within the oatmeal stout subgroup are two related substyles: British (or Scottish) oatmeal stout and North American oatmeal stout, and a unique substyle: malted oat stout. That’s three substyles in all, the subjects of this column.
British & North American Oatmeal Stout
British oatmeal stout was first brewed in Scotland in the mid-1800s. Several English brewers–Beartown, Samuel Smiths, and Youngs, for example–also make it. One reason the Scots use oats in this beer is that the grain grows relatively well in Scotland’s climate, as opposed to barley, which does better south of the border (in England, for those who failed geography). However, the yield per acre of oats is less than that of barley. Hops, too, thrive in England’s, ahem, lovely climate, but are not terribly keen on Scotland’s.
Fitting neatly in to a pattern, this style has a lower alcohol content than oatmeal stouts brewed in North America, a practice repeated with North American interpretations of other British styles, IPAs (the subject an upcoming “Stylistically Speaking”) being a prime example of this sad trend. In the United Kingdom, alcohol content is 4.2 to 4.8 percent alcohol by volume, while in North America, it is 5.0 to 6.1 percent abv. This is in keeping with national preferences, Americans preferring their beers stronger than do the British.
Bitterness in British oatmeal stouts run 30 IBUs, and color, up to 170 SRM.
Predictably, in the British version, English-grown hops such as Challenger, Fuggles, Goldings, or Target are preferred to American varieties.
In North America, brewers either imitate British brewers by their choice of hops, or use American varieties that impart different aroma and taste characteristics to the beer, making it different enough to be classified as its own (sub)style. Conversely, there are British brewers who use aggressive American hops to great effect in some of their beers, but the results are un-British.
I will digress briefly on this point. This year I sat on the panel that judged milds at the Great British Beer Festival. Of the seven finalists, one had all the hallmarks of American Cascade hops, distinct grapefruit notes on the nose and strong citrus elements on the palate. The beer was delicious, but all six judges, two of whom were experienced brewers, immediately pointed out that the beer was not a British mild, nice though it was. Christine Applegate, not The Blonde.
To return to my subject, many North American craftbrewers have taken up brewing oatmeal stout, and with good reason: oatmeal stout is delicious, goes down a treat for many drinkers, and lets the brewer display his skill. With as many as seven grains used to make oat-based stout, including the difficult oatmeal (it has a nasty habit of coagulating when boiled, which can gum up the works), plus getting the other bits of the recipe right, these sub-styles are not the easiest to brew.
An analysis of 33 American oat-based stouts revealed the following basic characteristics. color ranging from deep chestnut brown through opaque black; moderately light-bodied through moderately full-bodied; hop bitterness ranging from mild to moderate, the majority being mildly bitter. Expect to find all sorts of malt, dark and roasted grains, coffee, caramel, chocolaty, smoky, and even spicy notes on the nose and palate. As you can see, the style has been broadly interpreted by American brewers. In all respects, it is the opposite of the bland-tasting, narrowly defined North American standard and premium lagers.
Ingredients Make a Beer
Brewers use oats in two ways. Because of patent restrictions, the only way available to every brewery, but one, is to use a percentage of unmalted oatmeal in the mash tun. The other grains typically used to brew oat-based stouts are pale malt, almost always the main ingredient in every beer; chocolate, crystal, and black patent malts; roasted barley; and perhaps even a small amount, say, 3 percent of the total, of malted wheat.
Alastair Mouat, the director of brewing at Broughton Ales, describes the ingredients he uses to brew Kinmount Willie Scottish Oatmeal Stout, the flavors imparted to the beer from each, and his brewing technique.
“We use a blend of roasted barley and black malt (pale ale malt that has been roasted), along with ‘pinhead oats.’ Roast barley was used as ersatz coffee in the United Kingdom during World War II, and the coffee-like flavors in Kinmount Willie are derived from that roast barley.
“The flavor of black malt is more complex and often likened to chocolate. The overriding flavor of roasted barley and black malt tends to be somewhat harsh or bitter, and this is offset by the judicious use of hops and a certain amount of sweetness resulting from not allowing the beer to ferment out completely.
“The oats are used as a source of fats and oils which give mouthfeel and body to the stout. The oats are used in a milled form, which produces granules about the size of a pinhead. The critical factor is using enough oats to give the desired effect without using so much that the head retention is destroyed. We blend the oats into the grist along with the pale ale malt, roasted barley and black malt and mash in the usual way.”
Fred Gray, the brewer at Gray’s Brewery, uses rolled oats that are not pre-gelatinized, and adds them a half-hour before the end of the mash, at a rate of just over 11 percent.
The Maclay’s Variant: Malted Oat Stout
The patented second way is to use malted oats rather than oatmeal. The distinction is similar to the use of unmalted barley, developed by Irish brewers for use in their stout as a substitute for malted black patent.
This substyle of stout uses malted oats, instead of various forms of oats, in the mash. According to Duncan Kellock, who brewed Maclay’s malted oat stout until he went off to establish Forth Brewery, the beer was granted a UK patent in 1895. To his knowledge, it is the only patented stout in Britain, a unique brand. The brewery “originally marketed it as an invigorating health drink,” he said.
The brand is now contract-brewed for Maclay’s by the Dunbar, a Scotland-based Belhaven brewery with almost 800 years of brewing tradition. It is Scotland’s oldest brewery.
Unlike most stouts, which are black or nearly black, the color of Maclay’s Malted Oat Stout is dark ruby-brown. Malted oats make up 20 to 22 percent of the grain bill. Simpson’s is the only maltster still malting oats, but it is “on the wrong [English] side of the border, in Berrick on Tweed,” Kellock said mischievously. The Scots do like to get a verbal boot in on the English whenever they can.
Chocolate malt and roasted malt are also used. Both are easily detectable on the nose and palate. Compared to Irish stout, malted oat stout is sweet, much lighter in color, and it lacks the roasted barley that imparts the near-blackness and rich coffee aromas, characteristics with which most stout drinkers are familiar.
Bitterness is 35 IBUs and color is 50 SRM, quite a bit lighter than other stout styles, though still dark. Alcohol content is 4.5 percent and 1045OG.
There. Now choose your blonde, errr, I mean stout; pour it in a nicely cleaned glass; put your bottom down and your feet up; and imagine you’re north of the border–the Scottish one this time.