Although oats were used in British brewing for hundreds of years, most notably in Scotland and Yorkshire, by the nineteenth century they had fallen out of favor—that is, until the 1890s, when oatmeal stout began to pop up in newspaper ads such as this one from the _Aberdeen Journal, _Saturday, January 27, 1894:
“OATMEAL STOUT (Rose’s) most nourishing and strengthening, strongly recommended for Invalids. See medical opinions. Brewed from Oatmeal, Malt, and Hops only.”
Rose and Wilson of Grimsby and Hull appear to have been the only ones to brew an oatmeal stout at this point. Then Maclay, a relatively small and obscure Scottish brewery, brought Oat Stout to a wider audience in 1896. Their innovation was to use oat malt instead of the oatmeal that Rose and Wilson had used. Maclay was certainly very upbeat about its new invention, modestly calling it “The beverage of the Century.” Their health claims were equally enthusiastic:
“Its tonic properties are fully demonstrated in the marvellous results produced by its use in convalescent and in chronic wasting diseases, where its nourishing and stimulating effects are admirable …”
Maclay also took their patent very seriously, as this warning that appeared in the Falkirk Herald, Saturday, November 27, 1897, demonstrates:
“TO WINE AND SPIRIT MERCHANTS AND OTHERS … Public Intimation is hereby Given to all whom it may concern that the Sole Right to manufacture OAT MALT STOUT, or to USE this term, is secured to us by HER MAJESTY’S ROYAL LETTERS PATENT, that on and after this date any INFRINGEMENT of our PATENT RIGHTS … will at once be followed by proceedings for our protection.”
Not that the warning did them much good. Rival firms simply called their beers “Oatmeal Stout.” By the 1920s, there were hundreds of such beers on the market, many using Scottish imagery despite being brewed in England.
Stouts were already considered a restorative tonic, as is suggested by names such as “Nourishing Stout” and “Invalid Stout.” All the brewers, including Rose and Wilson and Maclay, played on the perceived healthy qualities of oats, but oatmeal stout was a bit of a con among London brewers. It contained such a tiny quantity of oatmeal—less than 1 percent of the grist—that its impact on the finished beer was nil. Maclay’s version contained much more: 13 percent of the grist in 1905 and a massive 33 percent in 1966.
Scottish brewers weren’t fans of complicated grists. With the exception of stouts such as this, their beers usually contained no colored malts at all, not even crystal. The most distinctive feature of this beer is the very high proportion of oat malt, accounting for a third of the grist. That must have been fun to mash. I suggest adding rice hulls to the mash to help runoff.
A stout (the name originally just meant “strong”) with an original gravity of 1.035 is a bit of a joke, but at least it’s been fairly fully fermented. Many Scottish stouts had less than 50 percent apparent attenuation.
Feel free to change the hops to any English variety that takes your fancy. The original brewing log doesn’t name the variety, just the grower.
1966 Maclay Oat Malt Stout
Batch Size: 6 U.S. gallons (22.7 liters)
Brewhouse efficiency: 72% efficiency
Apparent attenuation: 65.71%
3.375 lb (1.53 kg) pale malt
10 oz (284 g) black malt
2.375 lb (1.77 kg) oat malt
0.5 oz (14 g) caramelized sugar
1 lb (454 g) No. 3 invert sugar [substitute Lyle’s Golden Syrup or molasses]
0.5 oz (14 g) liquorice [brewer’s licorice]
0.5 oz (14 g) Bramling Cross at 90 minutes
0.5 oz (14 g) Bramling Cross at 60 minutes
0.5 oz (14 g) Bramling Cross at 30 minutes
Mash at 155°F (68°C). Sparge at 170°F (77°C). Boil for 90 minutes. Pitch the yeast at 62°F (17°C). Ferment for 4–5 days, then rack to secondary. Secondary fermentation is another 7–10 days.
Wyeast 1728 Scottish Ale or White Labs WLP028 Edinburgh Ale
The caramelized sugar is for color. Because the color of it will vary, depending on the manufacturer, the quantity is an estimate. Add enough caramelized sugar to hit an SRM of 40.
Add the brewer’s licorice in the last 15–20 minutes of the boil.