Recreating a 16th-Century Irish Brewhouse
Two months ago, researchers released the report of a remarkable project headed by Susan Flavin, Principle Investigator at FoodCult. She was curious about a major source of calories for people living in Ireland in the 16th century—beer. As the paper, published in the Historical Journal (Cambridge University Press), assiduously documents, many sources describe consumption patterns of the era. People drank a lot of beer then. Laborers doing hard work like masonry drank the most—up to 15 pints a day—but estimates of 10 pints hardly seem unlikely. But these estimates really beg a further question, one Susan and her team took years to answer: what kind of beer was it?
Continuing her careful research, she began to put together ingredients and equipment that would have been typical of the time, had artisans build a model of the 16th century domestic brewhouse, and set about making the beer. The press accounts who have covered the project focus on the beer her team made, some of which was stronger than people guessed (5.3%), but for people of a certain bent, that’s actually one of the least interesting findings. Her research uncovered things I didn’t know and stands as a singular effort in recreating ales of past centuries. These projects are valuable not because we get a mouthful of what beer tasted like almost 500 years ago (as careful as her project was, we can’t know that), but because going through the effort surfaced so many fascinating facts we can now confirm.
Ingredients
The biggest challenge in recreating ancient ales is trying to find ingredients that would have been typical of the time. That’s hard, because people cultivated different grains and hops then, and processed them differently as well. Nevertheless, her team chose to source Scottish bere barley, an old landrace grain that dates back centuries earlier than their window, and was cited by at least one 17th source as a standard variety in Ireland at the time. Ah, but in researching the barley, Susan discovered something important. Irish beer at the time used oats:
“In the Fitzwilliam household between January 1574 and October 1575, the total volume of malt in each of the ninety-one brewings was equally divided between barley and oats. Where the beer in the Irish accounts may be somewhat distinctive is in the type of malt used. Specifically, Irish beers contained a high proportion of oat malt in relation to barley. This would have affected the flavour, nutritional content, and the alcohol level of the resulting drink.”
Unfortunately for the project, she couldn’t track down what kind of oats the brewers may have been using, and resorted to modern varieties. Oats grew well in Ireland, and were a big part of the grists until the end of that century, when they began tailing off.
The next bit was the most surprising part. Malting has undergone some of the most important changes in beer technology, affecting not just the flavor but ferment ability and strength. (Ron Pattinson, for example, documented how under-attenuated 19th century doppelbocks were). So how did she malt the old landrace bere barley? Germination was straightforward, but then:
“The last step was kilning, which halted the germination and dried the malt. Although building an early modern malthouse would be a worthwhile venture, it was outside the scope of this experiment. The bere was shipped to Warminster Maltings in Wiltshire, the oldest operational malthouse in the UK and one of a few establishments still using traditional floor-malting methods.”
This was the first act I wondered about. Hadn’t malting changed quite a bit since then? Floor malting is an ancient, ancient practice, but kilns have evolved a lot. Barley kilns in the UK, and what are now Germany and Belgium, seemed mostly to have been open-fire arrangements that smoked the malt at that time. So sending it off to a place with “modern” indirect-fire kilning seems like a misstep. Or maybe not:
“Warminster's set up compares well with what is known about excavated Irish malthouses. They were also arranged along an in-line model, with a steeping trough adjacent to a clay-tiled germination floor, with a kiln nearby.“
This sentence includes a footnote leading to a report on this archeological site from the 1620s, which does seem to describe an indirect-fire kiln (though there are no pictures and I was slightly confused by the description). Irish pale ales in the 16th century—who knew?
Next, they selected what seemed to be a yeast strain with appropriate genetics for the region. They chose Tolhurst hops, an old variety, because it had Flemish ancestors. And here we come to another fine detail. Hops had mostly conquered continental Europe by the 16th century, but the English were still in transition. It makes sense, then, that the Irish brewers would have imported it from the continent, not England. “One of the Dublin Castle accounts from 1591 described hops that were ‘Flemish’ in origin,” the authors write, consonant with the expected timeline.
Brewery and Brewing
I won’t go into as much detail on the equipment and process Susan and her team used—though it’s really worth clicking through for the whole process. One detail deserves mention. This was long before sparging became routine (the process of washing the sugars from the malt with warm water). Instead, brewers soaked the malt, drained it and repeated the process another time or two, pulling successively weaker worts each time. The writers detail the equipment mash equipment at the time (“‘long tap,’ also called a tapstaff or mash staff, ‘huckmuck’, and tube tap”). They chose the tube tap and detail how it worked, including the use of a “wilch,” seen in the photo above. Cool stuff:
“With this method, the tub has a hole towards the bottom of one of the staves. A tube and tap are fitted into this hole. Withdrawing the tap allows wort to flow from the tub. Affixed internally to the back of the tube is a ‘wilch,’ a woven wicker filter. Aside from general mentions of wort sieves, few sources point to which system was used in Irish brewing. But imports from the 1560s of large quantities of ‘taps and cannells’, in tandem with rising inward shipments of hops, implies the use of similar technology. Models for a tube tap and wilch are scarce. However, there are published images of historic brewing equipment, and surviving examples at the Museum of English Rural Life and the Museum of East Anglian Life.”
Once they’d assembled information about brewery design, it took three years for coppersmiths, woodworkers, a cooper, and wicker-weaver to craft the equipment. (See photo at the top of the post.)
draining the wort. Source: Susan Flavin
They faithfully recreated the brews from the source material they had. They brewed on the system multiple times, starting with modern ingredients to get the hang of things. The process was pretty straightforward, but they could use modern instruments as the went, to see how the old instructions worked. For example: “The water was brought to a boil then allowed to cool in the copper ‘till the steam is near spent, and you can see your face in it’. When checked with a thermometer, the water was ready at 60–70° C.” That range is 140-158° F, which is smack-dab in the center of conversion. (Though it’s worth noting that you’d get better results if you got it exactly in the middle (65/149°)).
They brewed three times with the bere barley, oats, and Torholt hops, and describe the resulting beer as having “a slightly bitter taste, with a gentle flavour from the hops. They had a light honey colour and were hazy, probably due to the oats.” Brewers got a range of gravities—given the lack of a thermometer and the primitive equipment, that’s no surprise. I get a range of gravities on my homebrew set-up, and it’s more advanced. One of the batches was very low, but the two others were pretty close and produced beers of 5% and 5.3%. With experience, brewers could probably start hitting gravities more consistently as they went.
The researchers wanted to investigate the question of what kind of beer people were drinking in the 16th century more from the perspective of culture and nutrition. That’s interesting, but from where I sit, the experiment was more valuable to the brewing historian in seeing how people made beer five centuries ago. It was certainly rich with new info to me.
Finally, if Susan would like to conduct more research on that brewhouse she commissioned for the project, I know a few people who would be happy to keep brewing on it. You know, in the name of science.