The story
Oats were used in brewing for centuries, especially in parts of Europe where barley was scarce. But oatmeal stout as a named style arose in late 19th-century Britain, when brewers marketed stouts with oats as nourishing beers. Advertising frequently suggested oatmeal stouts were good for invalids and nursing mothers — claims that reflect the era, not modern nutrition science.
The style faded by the mid-20th century. Its revival came in 1980, when Samuel Smith’s in Tadcaster, Yorkshire, brewed an oatmeal stout at the request of American importer Charles Finkel of Merchant du Vin. It became an instant classic and inspired many American craft brewers to add oats to their stouts.
What it tastes like
The star is texture. Oats give the beer a silky, smooth and full mouthfeel that feels almost creamy. Flavors include coffee, chocolate and roasted grain, with a gentle nutty or toasted-grain sweetness from the oats themselves. The roast is typically softer than in a dry Irish stout, and bitterness is moderate. Sweetness varies by brewery, from fairly dry to noticeably sweet. Color is dark brown to black, with a thick tan head.
How it’s made
Brewers combine pale malt with roasted barley, chocolate malt and crystal malts, then add oats — usually flaked oats — often making up around five to twenty percent of the grain. Oats contain proteins, oils and beta-glucans, which contribute body and silkiness. Some brewers toast the oats first for extra nutty flavor. Because oats can make the mash sticky, rice hulls are sometimes added to help the wort drain. English hops and English ale yeast complete the recipe.
Fun fact
The amount of oats in some historical “oatmeal stouts” was reportedly tiny — in a few cases, barely enough to justify the label. Today, many brewers go the other way, and oats have become a key ingredient in hazy IPAs, too.