The addition of adjunct grains to beer can be a target of both scorn and praise. Macrobrewers’ use of corn or rice, though originally practiced out of necessity, is ridiculed by craft-beer lovers. On the other hand, history has shown that adjunct grains have been used as a means to nutritionally fortify, stretch barley supplies, or simply to add complexity to a brew. Some such brews proudly proclaim these supplements by name or appearance.
Oatmeal stout is fuller than a traditional dry stout, not as formidable as an Imperial stout, and quite complex in its own right.
Oatmeal stout does just this. Oatmeal enhances a beer on several levels. Oatmeal stout is fuller than a traditional dry stout, not as formidable as an Imperial stout, and quite complex in its own right. It is rich enough to serve as a winter warmer, and refreshing enough to restore. Some of the most famous ones are also widely available.
Oats was undoubtedly a common ingredient in ancient ales, as it was abundant, and beers made solely of barley weren’t necessarily the norm. As barley became the predominant brewing grain, others were phased out. But it should come as no surprise that oatmeal found its way into stouts later on. Oats is a staple crop in the cool, maritime, breezy, and sometimes harsh climates of Scotland and England. The further north one goes, the more prominent oats becomes as part of the cuisine. It is quite nutritious and valuable as a foodstuff, as it contains high amounts of both protein and oil. This is both blessing and bane to brewers, as will be noted later.
Coincidentally, these very same regions are the birthplace of stout and its forbear, porter. The marriage of oats and stout has waxed and waned over the past couple of centuries, and hopefully is here to stay given its popularity and the current state of brewing exploration. Of course, an oatmeal stout is still a stout, first and foremost, which was originally a strong porter. That legacy is among the most important in brewing history, and is one worth exploring briefly to define the evolution of stout.
Though stout was first mentioned in brewing annals in 1677, it was really a reference to the heartiness of the brew, and was actually a stout porter. During the 17th and 18th century cusp, porters were essentially the macrobrews of the day. They were made from a pool of malted barley that varied in color, flavor, and fermentability as malting technology was rudimentary at best. The malt was generally brown and somewhat smoky. Brews of assorted strengths were aged and combined to get a desirable blend. Aged, fresh, strong, weak, and any combination therein were game for the mingling.
Brewing lore credits a brewer by the name of Ralph Harwood, with producing a beer in 1722 at the Bell Brewhouse in London, which he named “entire butt,” as it was singularly batched and served. The beer was tabbed “porter” for reasons that are still up for debate, and was a rather dark beer relative to some others of the era.
Porters were also brewed in Ireland during this same period and the first reference to stout as a distinct style was noted in 1750 as a “stout butt beer.” Perhaps the dovetail between porter and stout began there. Made from a blend of pale, amber, and brown malts, neither stout nor porter was quite as we know them today.
The final innovation to forever change the formulation came in 1817, when a kiln was invented that was able to roast barley without direct heat. Further kiln refinement allowed maltsters to make pale malt. Hence, a combination of pale malt and a small measure of roast was all that was necessary to produce a consistent, high-quality stout. Today, this is essentially the recipe used for the dry Irish stouts such as Guinness, who shortened the name of their Extra Stout Porter to Extra Stout.
Over time, substyles of stout emerged and today there are several recognized. Near the end of the 19th and into the early 20th century, brewers, perhaps as a way to garner more market share, began to tout various forms of stouts for their health benefits. Primarily, these were milk stouts, which contained a measure of lactose, said to be of particular benefit for nursing mothers. These stouts were sweet because of the fact that lactose is unfermentable, and stout-drinkers developed a taste for brews that were not as dry as the traditional versions.
Some brewers began using oats, or more specifically, oatmeal in their grists, an ingredient that provided some of the same sweetness, but also even more complexity. Oatmeal stout, along with other sweet stouts, grew in popularity throughout the first half of the 20th century, but saw a decline thereafter to the point where they all but disappeared by the mid 1970s, when Eldridge Pope made the last one. The hiatus was brief, as Samuel Smith commenced production of their Oatmeal Stout in 1980. It served to revitalize the style, and today is brewed by quite few English brewers, including Young’s. It wasn’t long before the American microbrewing movement took hold and propelled the style further into the spotlight. Many American breweries today make outstanding versions, some of which are as loftily-regarded as their counterparts abroad.
Oatmeal is a gelatinized form of oats, in which the raw grain is cooked and then flattened, rendering the starches suitable for breakdown by the amylase enzymes in barley. As a brewing ingredient, oatmeal is one that is used sparingly, but has a marked desirable influence on the finished product. The high protein content is coveted because of the influence it has on the head and head-retention. Protein creates a thick, mousse-like foam that is less likely to disintegrate. As protein is unfermentable, it also lends a viscous impression.
Protein is also a potential culprit in a mash in that it tends to form a gluey mass that prevents proper drainage. The lack of husk exacerbates that situation.
The higher oil content of oats provides a silky-smooth, almost slick mouthfeel, and one that acts synergistically with the excess protein to produce a full-bodied, rich brew that is slightly sweet, but not cloying. Oatmeal is usually used at less than 10% of the grist, with 5% or so being about the norm.
Oatmeal stouts are more substantial all around than Irish dry stouts, though not terribly so, with slightly less roast character. They are just as dark, with chocolate and deep crystal malts often making up for the lack of roast in color, with the added benefit of more complexity. They might almost be thought of as a light version of Imperial stout.
The hop rate is fairly modest, with the focus on bittering rather than aroma. American brewers might buck this trend a little bit, but in general, the emphasis is on the multifarious malt bill and richness therein. As with most English/American sibling beers, each will take on the overall character of their respective homeland. Alcohol by volume is between 5 and 6.5% in the finished beer.
Oatmeal stouts offer something different for stout-lovers. They are neither one-dimensional nor overwhelming, and it would be hard to find a better constituent to temper the traditional full-roast flavor than oatmeal. They are contemplative enough to consume as a nightcap, and modest enough to session over. With winter looming, they might be the perfect option for those cold evenings.