In 1873, the manager of an ironworks in Söderfors, Sweden, was about to retire. When handing his responsibilities over to the next manager, he worried about one issue in particular: the future of a beer barrel.
This was not just any barrel, he explained in the letter to his successor. This was a barrel he had been given by the previous manager when he himself took over the ironworks half a century before, in 1820. In fact, he wrote, the barrel still contained beer from when it was first filled—in 1794.
What the retiring manager wanted was for his successor to continue taking care of this barrel. To do so, every other year, he needed to pull off half the barrel’s contents for drinking, then brew new beer to refill the barrel, and “well maintain it.”
Those three words were underlined in the letter, just to make it clear how strongly he felt about it. His desire was for this 79-year-old barrel to be passed on to coming managers of the ironworks “from each to each, into the remotest future.”
How far the manager got his wish is not known, but in 1952 the barrel—by then more than 150 years old—was still being maintained in Söderfors.
The Swedish Solera
This all might sound more than a little odd. The practice of drawing off some aged liquid and adding some fresh—but never fully emptying the barrel, so that the contents are fractionally blended over many years—is called “solera.” Most people associate the practice with Spanish sherry, but it has analogues in France, Portugal, and elsewhere. But why was this going on in Sweden? And why at an ironworks, of all places?
As you might have guessed, there is quite a story behind it.
Sweden was one of Europe’s great powers in the 17th century, ruling an empire that surrounded much of the Baltic Sea. For a century, Sweden’s largest city was Riga, which is today the capital of Latvia. One of the things that enabled Sweden to expand like this was its iron mines and ironworks, located in a belt just northwest of Stockholm. Söderfors, as it happens, was in the midst of this belt.
It wasn’t always that way. In the 1500s, Sweden didn’t have such a highly developed iron industry. So, the Swedish kings invited specialists from the Low Countries and Germany to settle in the iron belt. One group of immigrants was known as “the Walloon smiths” because they came from Wallonia, a region in the south of modern-day Belgium. That region was long famous for its iron production.
These Walloon smiths soon found themselves craving a type of beer they had enjoyed at home but couldn’t get in Sweden. This beer was barrel-aged for a year or two to become highly aromatic and quite acidic. Belgium, of course, is home to certain traditions that resemble that description, including lambic and Flemish red ale. It might be that they share an ancestor with that now-lost Wallonian brewing tradition.
Somehow, this tradition was picked up by Swedish aristocrats who owned the ironworks, and they developed it further—into what they called hundraårig öl, or “hundred-year beer.” They maintained this beer via the solera method, passed from generation to generation and highly valued. It was traditional for these wealthy families to drink the beer for Christmas out of small wine glasses, just as they would do with particularly noble wines. The drink even drew praise from the artist Johan Sergel, who was supposed to have exclaimed, “It is poison, give me more!”
If there’s one thing that rich people like to do, it’s show off—and it must have been impressive to be served beer out of barrels that were many decades old.
An Aristocratic Tradition
I often talk about how I see our brewing history as being divided in two: farmhouse brewing and modern brewing. In reality, however, there are three types, and the third is what I’ve taken to calling “manorial brewing.” It’s even more overlooked than farmhouse brewing, and that’s really saying something.
All over northern Europe, aristocratic families had large estates, and they kept themselves, their guests, and their workers supplied with beer brewed on those estates—usually from their own grains. These manorial brewhouses had economic and social incentives that were sufficiently different from those of modern brewing and farmhouse brewing, such that in some cases they ended up producing their own styles of beer. The hundred-year beer is just one example.
Another is the English October beer, which was a manorial beer that was barrel-aged for years, essentially for purposes of showing off. It even developed into what was known as “maturity ale,” a beer brewed on the birth of the eldest son and tapped when he came of age. October beer, famously, was the precursor of IPA.
As for how hundred-year beer was brewed, there is an account from 1952 that describes the brewing in Söderfors. They used 60 kilos of malt and five kilos of hops to make 75 liters of beer. (For a five-gallon batch, that would be about 33 pounds of malt and almost three pounds of hops, potentially hitting gravities above 1.150.) What kind of malt is not known, but one source used Vienna malts. The hops were most likely Swedish-grown and similar to landrace European hops in bitterness and aroma. In other words, this must have been a strong and bitter beer, although the bitterness must have faded quite a bit before anyone got to drink it.
The brewing began in the morning by stirring cold water into the malt. This was more laborious than it sounds; the source claims that in older times they didn’t mill the malts, but instead they crushed it against the side of the mash tun with the mash paddle. This produced so much malt dust that it made the brewer “look like a snowman.” They finished this process by about 6 p.m. in the evening.
They left this mash until about 2 a.m., then they began adding 200 liters of boiling water, bucket by bucket, while stirring. Once this was done and the mash had settled, they ran off the liquid, brought it to a boil, and poured it back over the mash. They then stirred the mash, allowed it to settle, and ran off and boiled the liquid again—and they repeated this process 10 times.
Then they let the mash rest for two hours before drawing off the liquid and boiling it again. They moved the thick mash to the lauter tun and slowly added the wort, little by little, until it ran clear. This might be done by about 3 p.m. the following afternoon.
Finally, they boiled the wort with the hops until they had boiled off roughly half the liquid, reducing it to about 75 liters. This process must have darkened the wort and given it caramel aromas, as with the heimabrygg of western Norway. After boiling, the wort stood until the next afternoon, when it was cool enough for them to pitch the yeast. In 1952 they were pitching what they called “brewery yeast”—presumably modern ale yeast, probably English.
Once the beer had fermented for 24 hours, they opened the solera barrel, drew off 75 liters of aged beer, and added the 75 liters of new beer—which was probably still fermenting. They didn’t drink the old beer right away; they bottled and aged it for at least four years to develop the right aroma. Note that although the beer was bottled, it was not carbonated. Because of its acidity, people sometimes drank it mixed with about two tablespoons of sugar per liter—reminiscent of Belgian faro. However, it’s likely that barrels could be handled so that no additional sweetening was needed; other families were known to not use sugar.
The beer must have been very strong, and the source says they thought the beer was about 11 percent alcohol. However, it’s unlikely that all of these beers were brewed in the same way, and probably there was considerable variation. Another source, later, says that their beer was 6 percent ABV, and that the pH of the beer coming out of the barrel was 3.1—pretty sour.
How Aged Is Solera-Aged?
This beer was called “hundred-year beer,” but how old was the beer in the barrel, actually? The beer being tapped would be a mix of different ages—including a tiny bit from the first time the barrel was filled—so no single figure truly captures it.
However, if we assume that they replaced half the beer every second year, it’s pretty easy to calculate. Given perfect mixing, the average age of the molecules you take from the barrel will, after a decade or so, be very close to four years. The older the barrel is, the closer you get to four. The reason the figure is so low is that the oldest beer in the barrel is reduced by half each time you do this. So, after just 20 years, only 1,024th of the original beer is left. After 40 years, it’s only a millionth. It’s there, and it may add some kind of complexity, but there’s just not much of it.
So, would it be completely wrong to call this a “hundred-year beer?” Actually, no. We can work out how many water molecules there are in a barrel of 150 liters, and then we can compute how many times you need to remove half before the last one is gone. As it turns out, if you brew every second year, the oldest molecule that you’re ever likely to tap is about 184 years old. So, in a very real sense, that truly would be hundred-year beer.
When I first read about this beer in a book from 1968, I wondered whether any of these beer barrels might still be going. Perhaps, I wondered, if one toured the ironworking region of Bergslagen and knocked on the door of every grand mansion, might someone still have a barrel?
As it turns out, there’s no need to do that. The Hultén family in Hedemora has been maintaining a hundred-year barrel since the late 1990s. That barrel, in turn, comes from the Gedda family, which acquired it in 1860—but the barrel is reportedly from 1806. They believe it is the last barrel still being maintained. Hedemora, as it happens, is about 70 kilometers (43 miles) west of Söderfors, right in the ironworking region.
So, if you want a taste of hundred-year beer, how would you go about it? One way, of course, would be to follow the brewing and aging directions above, and to look forward to tasting a sip of true solera beer in 2043 or thereabouts. However, there is an easier way.
Keep an eye out for beer festivals with a Belgian theme held in Uppsala, Sweden, and travel to those. Because sometimes the Hultén family shows up serving their hundred-year beer.
If that sounds like altogether too much effort, the Hultén family says their beer tastes rather like Cuvée des Jacobins or Rodenbach Grand Cru. What a surprise that the descendant of the Walloon smiths’ beer should taste like Flemish red!