Tag Archives: lager

J.C. Jacobsen’s letter about pure yeast to Gabriel Sedlmayr

There is another letter from 1884 I came across in the J.C. Jacobsen archive of the Carlsberg Foundation, in which J.C. Jacobsen proudly tells Gabriel Sedlmayr of Spaten about his new pure yeast. I found it fantastic from a historic point of view because it gives insight into the circumstances, the background and what they thought was important about this new method of generating pure yeast. If you can read German, please directly read the original source, otherwise this is what J.C. Jacobsen had to say about this yeast:

J.C. Jacobsen called Gabriel Sedlmayr his “old master teacher” and thus should be the first one to learn about his new experiences in the deterioration of yeast.

Jacobsen brought his first bottom-fermenting yeast from Sedlmayr’s brewery (i.e. Spaten) to Denmark in 1845 and had used it since then without ever having to change it, all while producing excellent lager beer for the domestic market as well as export beer for export to India.

Only in last two years (i.e. since 1882) the brewery started having quality problems and their pitching yeast started getting contaminated by “wild cells”. So of course Jacobsen asked the question why he could keep the same yeast from 1845 until 1882, only for it to deteriorate since then? Nothing has changed in the brewhouse and the cellars, they are cleaner than ever, wort is always chilled rapidly and even the air is cleaned with a spray of ice cold salt water that filters it the point where it’s analytically clean. Even the malt is of fine quality.

The only change was that due to an unexpectedly high demand and insufficient capacity, he had to resort to brewing during more months of the week: until 1874, Carlsberg only brewed in 7 to 8 months “the old Bavarian fashion”, and until 1882, brewing was still limited to at most 9 months, from early October until late June. But from 1882 onwards, this had to be expanded to 12 months as the lagering cellars that were to be built weren’t finished yet.

And exactly these 3 more brewing months were the problem: in the gardens and fields in the wide vicinity of Carlsberg, lots of fruits were ripening during that time, in particular cherries, plums, pears and grapes, which came with a higher amount of fermenting microorganisms, some of them bacteria, others wild yeasts like Saccharomyces Pastorianius (sic!). These led to increased infections on the coolships, in particular since wild yeasts like S. pastorianus kept growing together with the other yeast.

The last few sentences are particularly interesting, as Jacobsen seems to use the “Saccharomyces Pastorianus” name to describe wild yeasts, not bottom-fermenting yeasts which would be the modern use of the name. Later in the letter, he uses “Saccharomyces cerevisiae” to describe the regular yeast at his brewery. This is something I’ve not came across, but seems to indicate how little the specific nature of bottom-fermenting yeast was understood at the time before single yeast cells were isolated and analysed.

Jacobsen then continues by explaining Hansen’s method of isolating single cells in Pasteur flasks (swan-necked flasks), and how Hansen had isolated one pure Saccharomyces cerevisiae as well as two wild yeasts, which, when propagated and used for fermentation, all produced very different-tasting beers.

The pure S. cerevisiae was then used as pitching yeast in the brewery and effected a “nice fermentation” that quickly clarified, with a suitable attenuation from 13.5% to 6-7% Balling and quickly clarification and the maturation casks. Jacobsen then proudly proclaimed that “from now on all the fermentation in my whole brewery will be done with this pure yeast, created from a single cell! Truly a triumph of scientific research!”

He also pointed out that because of these observations, he thought that the yeast in all breweries is somewhat infected with “more or less wild” yeasts, as at the time most breweries were brewing during the summer months, and even regular yeast changing brings no improvement to that.

Jacobsen also notes that “in the old days”, when no brewery in Bavaria would brew during the summer, changing yeast was also a rare occurrence. If breweries wanted to continue brewing during the summer, then at least a few breweries or research stations like Weihenstephan or Dr. Aubry in Munich should occasionally isolate Saccharomyces cerevisiae to create pure yeast.

He also announced to to Sedlmayr that he’d send him a sample of enough yeast for one fermenter as express freight so that he could get acquainted with it. Jacobsen hoped it would arrive in Munich in a good state, though he admitted he had no experience sending yeast on such a long journey, and would be happy to send him more of his surplus yeast in the future.

The yeast also came with information how it was used at Carlsberg: the yeast was pitched at 5°R (6.25°C). The temperature increased to 6.5 to 6.75°R (8.12-8.43°C), and then slowly subsided back to 4 to 5R° (5-6.25°C). A 13.5% Balling wort fermented down to an attenuation of 6-7% Balling within 10 to 11 days. Jacobsen also pointed out that Sedlmayr’s wort contained less maltose than his own, so Sedlmayr had to expect lower attenuation.

And finally, Jacobsen announced his travel plans (which he expected to be his last big journey): first he wanted to visit Johann Götz in “Oswiecim near Krakow” (he probably meant Okocim) and then travel from there to Vienna and Munich, and further on to West Germany and hopefully to Lyon and Marseille. He hoped to meet Sedlmayr in Munich, but if he didn’t meet him there, he’d try to catch him in his summer apartment to meet his “friend and master” once more.

I find this letter particularly fascinating for a few reason. First of all, it shows the great admiration Jacobsen had for Sedlmayr who considered to be his teacher from whom he learned about lager brewing and in particular about bottom-fermenting yeast, and how much he thought he owed Sedlmayr for his own success.

Second, it shows how durable repitching the same lager yeast was: as Jacobsen himself said, he never needed to change his brewery’s yeast, which he had gotten from Sedlmayr himself, in 37 years of brewery operation. He also knew that changing yeast, even though it was done, indeed used to be a relatively rare thing. That way, this new pure yeast was exactly the innovation the brewing industry needed, as more and more breweries were brewing beer all year long, and sooner or later other breweries also would have run into the problem of wild yeast contamination in their own pitching yeast. In retrospect, we now know how incredibly successful Hansen’s method of isolating single cells and growing pure pitching yeast really was, as the method was widely adopted by the brewing industry within just a few years.

Nowadays, only very few breweries repitch their house yeast without having purified it. Among lager breweries, all pitching yeast is grown from pure yeast strains, and having a choice in pure strains has become a commodity not just in the industry, but even for home-brewers.

And finally, we learn about the fermentation properties of the yeast itself, which is pretty close to what you’d expect from a bottom-fermenting yeast during the 19th century: relatively quick fermentation (just 10 days) at temperatures of at most 8°C, with a relatively poor apparent attenuation of 50-55%. At least in other beers of that time period, the attenuation only slowly improved during the lager period where the specific gravity dropped to 4 to 5°P and helped carbonate the beer. In my book about Vienna Lager, I put up the hypothesis that becuase of these properties, the lager yeasts at the time were most likely type 1 (“Saaz-type”) bottom-fermenting yeast strains, as they were better suited to the lower fermentation temperatures in fermentation and lagering cellars that could not be finely controlled yet.

J.C. Jacobsen’s letter to Gabriel Sedlmayr dated 7th May 1884 is a great example of what was new, innovative and exciting to brewers at the time that we now consider to be a given. It also shows how closely connected the European lager brewers were back then: Jacobsen and Sedlmayr communicating by mail, Jacobsen visiting Johann Götz and various people in Vienna, Munich and France, the recognition of Weihenstephan as an important beer research lab in Bavaria, etc. They were more than practitioners, but also innovators who were not afraid to share their findings with each other, all with the purpose of bringing the whole industry forward and lifting the overall quality of beer, but also improving efficiency within the industry.

Lager Beer Made In USA, Part 4: Notch Brewing, Session Beer Experts

This is the fourth part in my series about some of the excellent lager beer that we had on our trip to the US in June 2024. Our final stop was Boston, MA. One place my wife and I definitely wanted to visit was Salem (probably best known for the deadliest witch hunt in the history of North America) just outside of Boston, but it wasn’t for the touristy witch trial stuff. Rather, we wanted to go to Notch Brewing, known for brewing top-notch (no pun intended) examples of Central European beer styles.

Notch Brewing (Salem, MA): Session Beer Experts

Unlike the previous visits at Dovetail, Goldfinger, and Live Oak, I did not know anyone at the brewery, didn’t get in touch previously, and wasn’t introduced by anybody. Notch were also the only ones of these that didn’t serve a Vienna Lager at the time of my visit (it is apparently a thing, though, according to untappd), so this was just a visit for our own quiet enjoyment.

After just 35 minutes on the train from Boston North Station to Salem and another 15 to 20 minutes of walking we arrived at the brewery that had only just opened. My plan was clear: to try as many of the classic styles as possible. Fortunately, Notch makes this very easy as most beers are between 4.0 and 4.5% ABV, and are optionally served as Schnitt/šnyt.

A view at the menu at Notch, with a long row of beer glasses on two shelves underneath.
A view at the menu at Notch, with a long row of beer glasses on two shelves underneath.

Louise’s first choice was Ungespundet, Notch’s take on a Franconian Kellerbier, while I went for Tenner, a 10° Czech-style pale lager. That beer strength is known in Czech as desítka, of which “tenner” is a direct translation.

We sat down with our beers in the gravelly beer garden that was set up with classic German beer tables and benches and wide sun umbrellas, right next to Salem’s harbour.

The Tenner was perfection. I feel like a broken record over the 4 parts of this series, but that beer was a great example of a 10° Czech pale lager, formulated and brewed by someone who obviously understands the style very well and enjoys it themselves.

A Notch-branded Willibecher of Ungespundet next to a Tübinger glass of Tenner.
A Notch-branded Willibecher of Ungespundet next to a Tübinger glass of Tenner.

Louise equally enjoyed her Kellerbier, and after I tried it as well, we both came to the conclusion that it bears resemblance to pre-2021 Mahrs aU. It is obviously not a direct clone, but again a beer developed by someone who knows their Franconian beers very well (and frankly speaking, Notch Ungespundet would fit perfectly into any Franconian Bierkeller).

That someone is Chris Lohring, a 30 year veteran of the Massachusetts craft brewing scene. Much has been written about him and Notch, like this article by my friend Joe in the Brewing Industry Guide, or this brewery portrait in Good Beer Hunting. And he’s certainly a man with strong opinions, like in this podcast episode of Craft Beer & Brewing (and I’m not somebody to agree with all his opinions, but it’s a great source to gain a better understanding how he approaches brewing at Notch).

The view from the outside into the brew house at Notch in Salem. While the gate is open, access is blocked off with a yellow chain and a sign saying "Authorized Personnel Only".
The view from the outside into the brew house at Notch in Salem. While the gate is open, access is blocked off with a yellow chain and a sign saying “Authorized Personnel Only”.

After this first excellent thirst quencher, I went on to try other beers. As a big fan of Czech Dark Lager with some strong opinions about it (read about my favourite tmavý recipe which is probably the best beer I ever brewed), I of course had to try Notch’s version. While it was very good, it was also a bit too roasty for my taste. But that’s fine, tmavé pivo comes in many expressions, some sweeter, some drier, some more going towards chocolate and caramel, some more roasted, some stronger, some lighter, some brown, some black.

A Tübinger glass with Notch Tmavý. Thick foam sticks to the side of the glass, while the beer is a very dark brown that still lets pass through a little bit of light.
A Tübinger glass with Notch Tmavý. Thick foam sticks to the side of the glass, while the beer is a very dark brown that still lets pass through a little bit of light.

In the connected world of the 21st century, I’m always “on” with my Stammtisch friends, so when I posted pictures of Notch to our private Signal channel, including the menu, I almost immediately got a request what to try next. It was the Kölsch (served in a half-liter Willibecher, sorry purists!) that I chose. With only a medium bitterness, a hint of floral hops, and a restrained fruitiness from the top-fermenting yeast it was very convincing and I think captured the essence of good Kölsch. Probably the only two things that stood in the way of the beer not getting served by a Köbes in Cologne were where it was produced (i.e. not in Cologne) and that it was unfiltered and looked ever so slightly hazy. Nevertheless an excellent example of the style.

I then went on to try all the other beers that I could: I remember the German Pils as generally very good but not to the point where I remember anything specific about it (I did not take any notes, as this brewery visit was just about enjoying ourselves), while the Helles Rauchbier was memorable as what I basically perceived as a clone of Schlenkerla Helles. Ironically, Schlenkerla does not serve their smoked Helles in their Bamberg pub/restaurant at all, so getting a beer like that from draft anywhere always feels like somebody outsmarted Schlenkerla a bit at their smoked Helles game.

Finally, The Standard, their 12° Czech Pale Lager: it felt more full-bodied, more rounded out, and most importantly more balanced than the Tenner. And just like it, a beer that feels like it has teleported you back to Czechia. As it was the last one I had on site, I sipped it more slowly while we were playing a few rounds of skee-ball.

Just before leaving, we also asked for crowlers (1 quart cans that were filled and closed up right at the bar, and they’re meant to be consumed within 2 weeks) of The Standard, Ungespundet and the Kölsch to bring back home. We shared them with our friend Ben about 1.5 weeks after canning. Both Kölsch and The Standard held up really nicely, while the Ungespundet unfortunately did not travel so well and had developed a bit too much diacetyl that ultimately made it not as good and pleasant to drink as straight from the source in Salem.

As with the other breweries discussed in this series, Notch was fantastic to visit as a place that offers a wide range of Central European styles, all super drinkable, all as good as you’d find them in some of the best breweries where the styles originated, and all bundled in a single brewery taproom, like you wouldn’t find it in Europe.

So, what’s next?

This article concludes my series about the 4 best breweries we visited on our trip to the US in June 2024. But worry not, there will be an article with all the other breweries we visited and/or whose beer we drank that didn’t quite make the cut to warrant their own blog posts, because frankly, even though they weren’t quite as amazing as Dovetail, Goldfinger, Live Oak or Notch, there was still lots of great beer that we enjoyed in Chicago, Austin and Boston.