Tag Archives: franconia

My Kellerbier Experiment 2024

I don’t homebrew that much anymore these days, at most 4 to 5 times a year, and really only the beers that I absolutely want to brew and drink, which includes fixtures like an 8° Czech-style pale lager for summer and a Czech-style dark lager (which I brew with Ben) for winter. So there is really not that much room for experimentation, simply because I don’t have the time, the drinking capacity (I’m 40, it’s all about quality over quantity now) or the resources like free fridge space for fermentation and lagering.

But there have been a few things that I kept wanting to try out, all in the context of Franconian Kellerbier that I had learned about in the last year or so.

The first thing was when my friend Joe Stange visited Brauerei Knoblach just outside of Bamberg end of last year, and came back with the information that Knoblach generally uses a 1:1 blend of Pilsner and Vienna malt as a grist, that their water is fairly hard parts of the year, and that they rely on that hardness (though he couldn’t provide any concrete numbers, nor was I able to find any analytical data about the water of Schammelsdorf, where the brewery is located). I really like Knoblach’s beers, and I know its peculiar taste, so I was wondering whether these were two factors that played into it (Joe also published an excellent article about Kellerbier in the latest issue of Craft Beer & Brewing magazine which does not seem to be online yet, but as a subscriber myself, I highly recommend getting an online subscription).

The second thing was what I learned at HBCon earlier this year about how Mönchsambacher brewed their Weihnachts-Bock. The two things I wanted to incorporate were their mash profile (which I wrote about in July) and the water profile, which has roughly equivalent hardness of calcium and magnesium, and plenty of it as sulphates. Luckily, my local Berlin tap water has about the right calcium hardness, so all I needed to do was to add the right of magnesium to get my tap water roughly where the Mönchsambacher water is in terms of hardness and mineral composition.

The third point on my agenda of things to try out were Aurum hops, a relatively new German hop variety that was launched as more disease- and climate-resistant with a “highly fine” aroma. As a daughter of Tettnanger, it is meant to replace Tettnanger and similar varieties, and German hop growers as well as hop merchants have been promoting it because they see it as a variety better suited to climate change than others, including German landrace varieties. What I wanted to know was well the hops fared in a traditional style.

I know, integrating all three elements in a single experiment is not exactly scientific, as I don’t have a baseline to compare it to, nor do I isolate any of the multiple variables. I’ll still call it an experiment simply because I want to know what a beer brewed that way would taste like.

And that’s how I formulated the recipe:

The grist was simple: 50% Pilsner malt, and 50% Vienna malt. As hops, I used Aurum hops, with additions at 60 minutes for bittering, 25 minutes for flavour, and to the whirlpool for aroma, which should end up at 41 IBU (calculated):

  • 2.3 kg Pilsner malt
  • 2.3 kg Vienna malt
  • 30 g Aurum hops (5.8% alpha acid) @ 60 min
  • 30 g Aurum hops (5.8% alpha acid) @ 25 min
  • 40 g Aurum hops (5.8% alpha acid) @ whirlpool for 20 min

My tap water needed to be enriched with magnesium, so I simply spiked the mash with food-grade epsom salts (MgSO4). According to my calculations, 18g should get me the right amount of magnesium hardness for 22 liters of beer.

As yeast, I used the Fermentis S-23 dry yeast strain. It’s not my absolute favourite, but it’s all I had at hand, also because I had forgotten to order anything else, which is all my bloody fault.

When it came to mashing, I just stuck to the Mönchsambacher mash profile, a single decoction mash. I boiled the wort for 60 minutes, then cooled it down to 6°C, pitched the yeast, and let it ferment at 10°C until it was finished fermenting. I then ramped down the temperature to 1°C for a week, and bottled it with wort I had held back for bottle conditioning.

The resulting beer has an OG of 11.6°P (slightly lower than a typical Kellerbier, but that’s mainly from me buying the ingredients and only afterwards deciding on a mash profile with a slightly lower efficiency than my regular double decoction mash), and fermented down only to 3.5°P FG, resulting in just 4.3% ABV.

A Willibecher of the Kellerbier. The colour is golden with a tiny bit of haze, with a moderately dense head of foam on top.
A Willibecher of the Kellerbier. The colour is golden with a tiny bit of haze, with a moderately dense head of foam on top.

A first taste test showed that the experiment, in my opinion, was successful: the beer has a minerality and a maltiness very much reminiscent of Knoblach and Mönchsambacher. The same goes for the bitterness: while it’s not quite as pronounced as I hoped it would be (I blame the low attenuation which probably leaves just enough residual sweetness to slightly mute it), as it is very lingering: even minutes after, that hop bitterness just stays on your tongue. Which is exactly what I appreciate so much about these beers.

As for the hop aroma of Aurum itself: there’s not that much there. Even though I kept the hops in the fridge and sealed at all times, it was not the freshest batch (2021 harvest), so that may have had an influence. Still, the bitterness the hops provide was quite on point.

Still, I’m very happy with the end result. I think it shows that the local water profile of Bamberg’s surrounding area has a large impact on the flavour of the beer, as long as breweries don’t soften or otherwise treat the water and embrace their very local water profile instead (which is one of the points that Joe makes in his article).

Even the yeast played out alright: I didn’t like S-23 in the past because it can produce rather fruity fermentation byproducts. In this case, the beer came out fairly clean, just with a high final gravity. In retrospect, that actually wasn’t too surprising, as S-23 is the closest known relative of the Wyeast 2001 strain, which is purported to be the Pilsner Urquell “H” strain, and is also known for relatively low attenuation.

My take-aways of this brew are the following:

Hard water, especially similar to the Mönchsambacher water profile, can get you a flavour profile in beer that is similar to the slightly rustic flavour profiles of beers like Mönchsambacher, Knoblach and others in the region.

The combination of Pilsner and Vienna malt probably adds to that rustic character.

A lower attenuation seems to help with the style, but another experiment to try out a more highly attenuating yeast should bring more clarity.

Aurum hops are probably okay for standard German styles, but also require more experimentation to understand their exact aroma potential and how to use them. A more recent harvest would be great to try next time. I generally support the idea of hop varieties that are better suited to climate change (which is an inevitability that will hit the brewing industry hard in the decades to come, so good on German hop breeders to be as forward-thinking as that), as long as we understand well enough how to apply the hops to get the same aromas and flavours as with more traditional varieties.

Lager Beer Made In USA, Part 1: Dovetail, Franconian at Heart

My wife and I spent the first two weeks of June 2024 in the US for our holiday. I got this trip as a gift for my 40th birthday last year from my lovely wife (lucky me!): we started in Chicago, IL, then went to Austin, TX, and finished the trip with a few days in Boston, MA.

I could tell you all the details of my trip, and how absolutely amazing it was, but this is not a travel blog. I rather want to talk about beer. More specifically, about lager beer, because that’s what interests me, and that’s what I want to drink. So that’s what I did: lager beers of whatever style available was my first choice when ordering beer in the US. I had plenty of excellent ones, some good ones, some okay ones, and some bland and boring ones. So let me tell you about the outstanding ones, about 4 breweries that I was very much interested in from the start, and which did not disappoint. This is part 1 of a series of articles that I intend to publish in the next few weeks.

Dovetail (Chicago): Franconian at Heart

I had heard about Dovetail quite a few years ago, everyone I know who had visited there had told me that their beers were excellent, so naturally, I just had to go there as well. As I had previously communicated with them by email, I mentioned my intention to visit and say hello, and was invited for a tour around the brewery.

On our first full day in Chicago, our plan was to watch a baseball game (Cubs v Phillies) and then to visit the brewery for a few beers afterwards (Dovetail isn’t far away from Wrigley Field, the Cubs’ gorgeous historic stadium), which is exactly what we did. After ordering our beers (Vienna Lager for me, of course), we were greeted by Jenny Pfäfflin (one of Dovetail’s employees who I’ve known on social media for years) and Hagen Dost and Bill Wesselink, the brewery founders. We were chatting and trying out the beers. By coincidence, another group of people from Canada also visited the brewery to meet Hagen et al, so we also got to say hello to them. It was a pleasant surprise to discover Jordan St. John in the group, who I had followed online for years. The beer world seems so small when something like that happens.

We were eventually shown around by Hagen and Jenny in a private tour of the brewery. Dovetail’s brew kit is very German: a mash tun, a lauter tun, a kettle, and a holding vessel.

Dovetail’s brewing system. From left to right: holding vessel, kettle, mash tun, lauter tun. They are accessible through a gallery via stairs. On the front, a computer panel is installed. Next to the stairs is a small standing desk with lab equipment and documents.

Following a rather traditional vibe, the brew kit is accompanied by a coolship located upstairs, into which wort is pumped after boiling and left to cool there until it’s dropped to 75°C (167F) after which it’s pumped through a plate chiller and into open fermenters (accomplishing the traditional vibe).

As Hagen had to leave but we had so much more to talk about, he invited me to come around another day for me to witness some of their brewing. And that was truly exciting: sure, I got to see somebody brewing on the kit, but most excitingly, I witnessed wort being cooled in the coolship!

A happy looking Hagen Dost leaning against the side of the coolship which is getting filled with wort of the day’s first turn of Hefeweizen, while the room fills with steam.

In my conversation with Hagen, what became clear to me is how well he understands Bavarian and Franconian beer culture, and how much he’s done to discover some great breweries off the beaten path. He then showed us how a coolship was part of the plan when he was brewing with Bill before they had even founded Dovetail: on one side of the room, a small rectangular metal vat was leaning against the wall, which is what they used as a coolship when they still test-brewed on essentially home-brew scale.

But Dovetail isn’t just a German-style brewery: they will brew the classic Central European styles, whether they’re from Germany, Austria, Czechia or Poland, but also do spontaneously fermented beers in the style of Belgian Lambic (they don’t call it that, though). I didn’t try any of the sour beers, but I tried plenty of the others: Helles, Dunkles, Vienna Lager, Lager (their idea of a Franconian Landbier), Sticke (a slightly stronger Altbier), Kölsch, Rauchbier, and Grodziskie. Honestly, I couldn’t fault any of them.

The Vienna Lager is straight to the point: just Vienna malt and Styrian Golding hops. According to Jenny, they occasionally get people complaining how it’s not adherent to the BJCP style guidelines, and they’re right. But neither would have been historic Vienna Lager, and the BJCP is meant for competitions. Dovetail’s Vienna Lager has a certain minimalism about it that just makes it an easy-drinking, uncomplicated beer with the right amount of malt complexity to make it exciting and a beer I could’ve been drinking the whole afternoon/evening (if I hadn’t wanted to try many/most/all of their beers).

The Dunkles was equally good, and exactly what I’d expect in a Bavarian brewery. Hagen later told me it had been inspired by Kloster Weltenburg’s Dunkel. Their Lager was a kind of Helles, similar but different from their regular Helles, and definitely something I’d expect in a small Franconian brewery served as the #1 beer consumed in large quantities by most of the village. Sticke and Kölsch tasted like the Rhineland, the Rauchbier would probably be well-received in Bamberg (personally, it reminded me more of Spezial than of Schlenkerla), and the Grodziskie wasn’t very different from the one I tried a few months ago.

But most importantly, all of the beers had character. They weren’t just very good, clean examples of their respective styles, they all had something about them that made them truly exciting to drink. Some cleaner, some maybe a bit rustic, but all of them with something that just screamed “this is the style in which we brew our beers, and we like it like that” to me.

That’s when I realised that there is something very Franconian about Dovetail, not just in the aspects of traditional brewing (like the coolship and the open fermentation), but also the “house style” that goes into them. At the same time, Hagen is very technically minded: he spoke to me about how they are very specific about certain temperature rests during mashing, such as alpha amylase rest (a mash rest at a temperature range that promotes the activity of alpha amylase, an enzyme that chops down chains of starch first into unfermentable dextrines and if given enough time, eventually into some fermentable sugars), as there are other things happening at around 72°C, such as the extraction of glycoproteins, which are relevant for head retention. Hagen even specifically spoke about glycoprotein rest and how important it was for their Hefeweizen which they brewed that day.

(Back home in Germany, I looked up glycoproteins in brewing literature, and really, Prof. Narziss mentions it in a few sentences in his book)

Four open fermenters in the fermentation room at Dovetail, accompanied by two yeast harvesting vessels.

Hagen also emphasised the importance of the coolship in removing DMS precursors from their wort. What I could contribute was to teach him the German term for that: “ausstinken” (lit. “to stink off”), and that it’s not only used to describe what happens in the coolship, but also in open fermentation, another traditional element Dovetail employs.

All in all, I was really happy with every single beer I drank at Dovetail. I also have to thank everyone at Dovetail, but especially Jenny, Hagen and Bill, for the friendly welcome we received. We actually brought a few cans of their Helles and their Vienna Lager back to Berlin, and they travelled quite well.

Thinking back, there is something quite special about a brewery like Dovetail, something that I wouldn’t be able to find the same way in Germany: I could go there to drink really well-brewed German, Czech, Polish styles, easily at the same level as a good, traditional brewery back in Europe. But unlike here, I could enjoy a whole range of local styles from all over Central Europe at the same time. I don’t know of any brewery that serves a Helles, a Kölsch, an Altbier, a Rauchbier, a Hefeweizen and a Grodziskie all at once, at an incredible quality.

A handled beer glass of Helles on the left, and a Willibecher of Vienna Lager on the right, both sat on coasters on the bar at Dovetail. In the background, a historic copper Grant with swan neck taps for lautering can be seen embedded in the wall.

How To Brew Mönchsambacher Weihnachts-Bock, according to the brewmaster

At HBCon 2024 (more about the event here), one of the sessions I attended was a seminar about how to brew easy-drinking Bockbier. Basically, brewmaster Stefan Zehendner told us all the details about the beer, the idea an concept behind, everything about the ingredients and the brewing process, and of course lots of little details and anecdotes.

A lot of information about that particular beer can already be found in this article in Craft Beer & Brewing, and if you’re a subscriber to that magazine, there’s even a home-brew recipe available.

Mönchsambacher produces a total of about 6000 hl of beer per year, with no intention of further growing the business. Of this, about 1,500 crates (i.e. 150 hl) is Weihnachts-Bock, which is usually sold out within a week.

The Weihnachts-Bock has about 17.5 to 18 °P original gravity. To achieve consistency, all the lager tanks are blended into one beer during packaging. It has about 3.3 to 3.5 °P residual extract, and is hopped to 48 IBU. Compared to the brewery’s other beers, this CO2 content is slightly higher, making this whole beer a hop-forward, not too sweet, well-integrated beer.

The brewmaster considers his brewing water to be one of the keys to his beer. The water is very hard: 28 °dH (German degrees of hardness), where 1° equals 0.1783 mmol/l. About 13 to 14 °dH are magnesium, and about the same amount is calcium, much of it bound to sulfate. This hardness results in a higher mash pH for the Bock, around 5.6 to 5.7.

The grist is simple: 100% Pilsner malt. As many other local breweries, Mönchsambacher gets their malt from local maltings Bamberger Malz. The grist is also used for all the other bottom-fermented beers, except for the Festbier, which is brewed from a 50/50 blend of Pilsner and Vienna malt. The Pilsner malt from Bamberger Malz is slightly less modified.

This is what the mash schedule looks like:

The grist is mashed in at 45°C, then rested for 10 minutes.

Then the mash is heated up to 52°C, for another 10 minute rest.

After this rest, the mash is heated up to 62°C, and the first (and only) decoction is pulled: about one third of the mash volume (relatively thin mash) is pumped into the kettle, brought up to 72°C and rested for 15 minutes for saccharification. It is then brought to a boil and boiled for 5 minutes before it is mixed back.

Stefan called this decoction to be important for the bright golden colour of the beer and a more robust (he used the word kernig which is impossible for me to translate) body.

After mixing the decoction back, the mash should have reached 72°C. It is then left to saccharify for another 20 minutes, after which it is heated up to 78°C, which is when lautering starts.

The wort is boiled for a total of 75 minutes. The only hop variety used in the brewery is Perle. In the case of the Weihnachts-Bock, the hops are added at 3 points: at the beginning of the boil, 25 minutes before the end of the boil, and in the whirlpool. The hops in the whirlpool are added beforehand, so it has 10 minutes of contact while the wort is pumped into the whirlpool, and then left for a trub cone to form for another 15 minutes until the wort is pumped out of the whirlpool.

The wort is then chilled to 7.5°C, yeast is pitched, and fermentation happens at 9.2°C. The brewmaster said the yeast strain they use is W-34/72 which they get delivered from Speckner yeast lab in Augsburg. I’ve not been able to find that particular strain in Speckner’s list of available strain, so this is probably a matter of miscommunication (Speckner has W-34/70 and W-34/78 in their portfolio). In any case, Zehendner finds the water much more important than the yeast, so for home-brewers, W-34/70 is probably totally sufficient.

What is important though is that the yeast must have gotten used to the brewery before it is used for fermenting the Weihnachts-Bock. So any yeast going into Weihnachts-Bock has been pitched once or twice before.

Fermentation takes 13 days in tanks which are left open, so it is effectively open fermentation. Before moving the beer into lagering tanks, Kräusen (freshly fermenting beer) from another tank is added at about 10% before it is lagered to ensure a very clean secondary fermentation/lagering. Lagering itself happens at 2°C for a total of 12 weeks, with fermentation slowly progressing for 10 weeks.

The last time this recipe has changed was when the brewery upgraded their brew system in 2000. As part of the adjustments, the number of decoctions was reduced from 2 to 1, and because they had sold the coolship, the hop addition had to be removed. Because there was no more coolship, the whirlpool was instead chosen to have a similar geometry so that the wort can “stink out” in the same way, so basically that DMS and other unwanted chemical compounds can evaporate in the same way and at the same rate.

When the beer is bottled, it is always unfiltered. Zehendner considers a bit of yeast to be absolutely vital to have a beer that can age well. Apparently, the beer will ferment a little bit more after bottling, so practically, the Weihnachts-Bock is a bottle-conditioned beer. The best before date is 3 months for the Weihnachts-Bock and just 5 weeks for the regular Lager. The main reason for the short date is that the beer changes in the bottle, and slowly loses its sulphur notes, making it taste different from what regular drinkers expect. Mönchsambacher also keeps their bottled beers chilled at all times, and are selling it chilled directly from the brewery.

Something that I had never heard before was the anecdote of a pediococcus infection they struggled with for about a year. Pediococcus is a bacteria that makes beer go “ropey”, it gives it a slimey texture and leaves behind plenty of diacetyl. They struggled with such an infection on and off for about a year, until they finally discovered the unlikely source of the infection: the water source! After spending about €80,000 on a membrane filter, this has finally been cleaned up and now the brewery is infection-free again. The brewmaster pointed out that the water treatment with chlorine dioxide would have been another option, but he decided against it specifically because he thinks that it could also negatively affect yeast health in the long run.

Still, this is the only time where I’ve heard that the infection vector of a brewery was the water. It is quite insidious: after disinfecting the whole brewery, all it needs is some water to rinse off disinfectants, and you got the infection back on your equipment.

Stefan Zehendner is not just a traditional Franconian brewer, he also likes to experiment: recently, they filled a batch of Weihnachts-Bock into a wine cask that was previously filled with spontaneously fermented Silvaner wine. In the future, he’s also thinking about producing Weihnachts-Bock wort and getting it fermented somewhere else as a sour beer, which also sounds absolutely intriguing. And apparently if you visit the brewery taproom at the right times, there’s a chance that a keg of Cantillon might be on, about the last beer you’d expect in Franconia.

The process I described here does not just apply to the Weihnachts-Bock, but their other Bock, the Maibock, is also brewed essentially the same way. The only differences are a slightly reduced original gravity of 16.5°P and a reduced bitterness of about 40 IBU.

And that’s how you brew Mönchsambacher Weihnachts-Bock, based on all my notes from the session at Heimbrau Convention 2024. I think this description is complete enough to brew a pretty faithful clone at home.

#BeeryLongReads2018: Revisiting Brewing Methods

More than two years ago, I wrote an article discerning accounts from 1834 about various brewing methods as they were practiced in Germany and Austria, in particular Munich, Augsburg, Prague and Vienna, as part of #BeeryLongReads. I even won great prizes for it:

A lot has happened since then, not only did I gain more experience in blogging, I also published a book about historic beer stuff. So this time, I want to follow up on the theme and discuss the specific differences in decoction mashing from a late 19th century point of view.

Franz Cassian published a book named “Die Dampf-Brauerei. Eine Darstellung des gesammten Brauwesens nach dem neuesten Stande des Gewerbes.” in 1887 in which he talks about the state of the art of brewing at that time. I only came across this book recently, and found it particularly interesting because it contains a whole section with nothing but detailed descriptions of various types of decoction mashing and their differences.

Now, if you’ve never heard of decoction mashing before, let me just quickly describe it to you: when brewing a beer, the brewer uses the enzymes in the malt combined with hot water to convert the starches in the malt to sugar. In order for the enzymes to work under optimal conditions, this needs to happen at certain temperatures. Different enzymes do their stuff at different temperatures, so if you wanted to activate the enzymes to do their thing, you’d go through these different temperature steps so that each of them can work under optimal conditions. There are essentially three different ways of doing this:

  1. by adding more hot or boiling water (which can make the mash very thin)
  2. by heating up the mash until the right temperature is reached (which can be tricky if you don’t have exact temperature control)
  3. by taking a part of the mash, boiling it, and mixing it back (which takes a long time and uses up a lot of energy and fuel)

Some brewing traditions even just keep a single temperature, but in some ways, they’re just a simplification of methods (1) and (2), which nowadays are called infusion mashing. Method (3) on the other hand is called decoction mashing and is very traditional in Bavaria, Bohemia and Austria to a certain extent, and only used to be practiced there. At the time, brewers swore by it and exclaimed that decoction mashing was absolutely essential for their local beer style. Even today, decoction mashing is necessary in the Czech Republic if a brewer wants to call their beer a Czech beer.

Modern German breweries have gone off it for various reasons though: energy efficiency is one of them, as infusion mashing doesn’t use up nearly as much energy. Another reason is the perceived lack of impact on quality. This is relatively controversial, but there exist studies that claim that the difference of decoction mashing and infusion mashing cannot be smelled or tasted by your average Joe beer consumer, while some brewers still swear by it. An experiment at Brulosophy that compared whether people could taste a difference between triple-decocted beer and one produced by single infusion mash failed to gain significance. Upon closer analytical examination, differences between worts and beers produced through infusion mashing resp. single, double and triple decoction mashing can be measured.

Decoction mashing nowadays is mostly distinguished by how many decoctions are pulled (1, 2 or 3), the consistency of the decoctions (thick or thin), and which temperature steps you’re going through. With modern brewing science as a helpful tool, we exactly know what’s happening at each temperature step and which enzymes will be the most active, and we know about the destructive force boiling a decoction wields on the diastatic power (the ability to convert starches to sugar) of the partial mash. Even though brewing science in the late 19th century had already made great progress, brewing as such was still a craft and findings of brewing science were not necessarily immediately incorporated into the knowledge and toolset of a brewer.

With this context, let’s look at what Franz Cassian wrote about the specific styles of decoction mashing. He distinguishes three main methods, the Munich method, the Viennese method, and the Bohemian method. He identifies two main differences between those three methods: first, the type of malt that is used in mashing, and second, the way the mash is treated in relation to temperature, the number and consistency of individual decoctions, as well as boiling durations. The rest of the operation, like boiling and chilling the wort as well as fermenting and lagering the beer, he says, are essentially the same.

He then goes on to describe the different malts that are used for each of these methods: for the Munich method, highly kilned malts are being used, while for the Viennese method, the malt used produces a beer with reddish-brown colour that is lighter than Munich beers. The malt itself is very aromatic. The typical malt for Bohemian beers, he writes, is very pale, leading to an almost wine-like colour of the beer. The malt is kilned as such low temperatures that the author describes them more as dried than kilned. He also mentions an interesting detail: some Munich breweries at that time had started kilning their malt to a lower temperature, and then adjusted the colour of the beer with Farbebier.

Farbebier, literally “colouring beer”, is an extremely dark beer made from large amounts of debittered roasted malt that can be used to adjust the colour of beer without imparting the beer with too much roasted aroma and flavour. Since it’s just beer, mixing Farbebier with pale beer was compliant with the Bavarian prohibition on adulterating beer or substituting its ingredients. It was the only legal food colouring for beer at that time, and still is to this day if you want to advertise your beer as being compliant to the Reinheitsgebot.

Kilning at lower temperatures has a good technical reason: it destroys fewer of the enzymes that are required for starch conversion, and makes the malt more convertible, which in turn makes it easier for brewers to work with it. Using Farbebier was really just for matching customer expectations. This is what some Munich breweries allegedly still do nowadays: American beer consumers expect an Oktoberfest beer to be amber-coloured instead of the golden colour of modern Festbier, so Farbebier is used to adjust the colour for the American exports without impacting the flavour.

This description with Bohemian malt being the palest, Munich malt being the darkest and Viennese malt being in-between these two also reflects modern base malts: many maltings in Germany will produce and trade at most three base malts: Munich malt, Vienna malt and Pilsner malt. Only a few specialty malt producers offer a wider range of base malts, from extra-pale malt even paler than Pilsner malt, to Pale Ale malts more suitable for British and American styles, to proprietary malt blends for producing wort with a distinct red hue.

Besides the malt, the even more important distinction in brewing methods was the mashing itself. For Bavarian mashing, the author distinguishes four types: the old Munich or old Bavarian method, the new Munich method, the Augsburg method, and the Franconian method.

Old Bavarian Method

At the time of the publication of this book, this method was barely in use anymore. It used to be common for primitive breweries with not a whole lot of equipment, so most of the work was manual labour: mashing and lautering was done in the same vessel, so mash tuns had a false bottom, stirring was only done by hand, and hot water was added through simple tubes attached on the side of the mash tun going underneath the false bottom. Underneath the mash/lauter tun, another vessel, the “Grand”, was installed, which was large enough to contain all the collected wort.

The brewing process worked like this: for every unit of malt (by weight), 8 times that amount in water was required. One third of the water is added to the mash tun, while the rest is slowly brought to a boil. While the water heats up, the malt is doughed in. Bringing the water to a boil could take 3 to 4 hours, so that’s how long the malt was doughed in at a cool temperature. When the water is boiling, it is added very slowly to the mash, and mixed thoroughly, so that when all the boiling water is mixed in, the mash is at a temperature of about 37 to 38 °C.

Immediately, one third of the volume (as a thick mash) is put back into the copper, and quickly brought to a boil, where it is boiled for half an hour and then slowly mixed back into the main mash while constantly stirring. The resulting temperature of the mash should then be at about 45 to 50 °C, and will be mashed (stirred) for another 15 minutes to liquefy the mash. Then again, a third of the volume (again a thick mash) is put into the copper, and boiled for 45 minutes, and again slowly mixed back to reach a mash temperature of 60 to 63 °C. More stirring happens for 15 minutes, until the the third decoction can happen:

A third of the mash, this time a thin mash, is put into the copper, boiled for 15 minutes, and – you should know the drill by now – slowly mix it back under constant stirring to reach 73 to 75 °C. With that, the mash boiling is concluded, but not the mash itself: it gets stirred until the mash is fully converted. Nowadays, this would be verified with an iodine test (an iodine solution turns from brown to blue if the mash still contains unconverted starches), but back then it was determined by how quickly the hard matter in a sample of the mash sinks down the bottom of the vessel.

When mashing is concluded, it rests so that the grains can sink to the bottom of the vessel, which usually takes 30 minutes. Then the tap of the lauter tun is opened and the first wort is drawn into buckets. The wort is poured back onto the mash until it runs clear, then the wort is collected in the Grand, from where it is transferred to the copper. The grains are then further rinsed by pouring hot water on top: 30 liters per 100 kg of malt. The resulting wort is added to the wort. More hot water is then poured on top of the grains, at 50 to 60 liters per 100 kg of malt, and the resulting wort is used to brew a weak beer called “Schöps”. The final runnings, at 30 to 40 liters per 100 kg of malt, are called the Glattwasser and are used for distilling.

New Munich Method

Unlike the old Bavarian method, the new Munich method employs more sophisticated equipment and a certain degree of automation using steam engines. Mash and lauter tuns are separate, and no full-sized Grand is used anymore. Doughing in happens with a pre-masher, and the initial mash temperature is reached by using water from a hot liquor tank. The Mash tun is set higher than other equipment so that decoctions can be transported using gravity, and mixed back using pumps. Like the old method, the new method still employs three decoctions, two thick ones and a final thin one. But due to the high degree of automation, exact timing, and a hot liquor tank that can be used for quick temperature corrections, the whole process is meant to be quicker and more precise and therefore more reproducible and repeatable.

The temperature steps are slightly different: the first decoction is drawn at 30 °C and boiled for 15 to 45 minutes to bring the mash to 55 °C. The second decoction is boiled for 15 to 45 minutes to bring the mash to 65 °C, and the final thin decoction is boiled for 30 to 45 minutes to bring the mash to 75 °C. The amount of sparge water that is used is two thirds of the initial water volume.

Augsburg Method

The typical method for Augsburg is “auf Satz brauen”, which is pretty unique and quite different from the class Bavarian or Munich decoction. The ratio of malt to water is 1:6 by weight. The mash tun has a false bottom, which gets covered with hop leafs to help prevent the mash from getting sour through lactic acid fermentation. Doughing in is done with so much cold water that the resulting mash is quite thin and easy to stir, and then rested for 4 to 5 hours. Then the cold malt extract (you probably can’t call it wort yet), called “kalter Satz”, is then drawn off and put aside. The rest of the water is brought to a boil, and then a few liters (unfortunately, the author is not very clear here) of the kalter Satz are added to the boiling water which makes the proteins in it coagulate. The proteins are removed, then the hot water is slowly mixed into the drained main mash that has been hacked up before. After all the hot water has been added, the kalter Satz is also mixed back into the main mash, after which it should have a temperature of 60 to 65 °C.

Then the mash is stirred until it has properly liquefied, only to rest 15 minutes before the “warmer Satz” is drawn off. This is just like lautering: first, wort is drawn off and poured back into the mash until it runs clear. Of all the wort, two thirds go into the copper, while one third is put aside. The wort in the copper is brought to a boil as slowly as possible to maximize the amount of hot break for a clearer wort. The boiling wort is poured back into the main mash, which again should have a temperature of about 65 °C. At that point, the mash shall be stirred to continue starch conversion.

Then, the thick portion of the mash is drawn off into the copper and boiled for up to 2 hours, until no more hot break appears on the surface. It is then mixed back into the main mash to get it up to 70 °C. Then, the wort that was set aside is added to the copper, hops are added, and the main mash is lautered and also added to the copper. This wort is then slowly brought to a boil.

In the late 19th century, this method was considered to be completely outdated, and only practiced in Augsburg. It was hard to scale it up to larger amounts, and suffered greatly from issues of the mash getting sour during the whole process. Beer made using it was described to be very full-bodied and less perishable than other Bavarian beers.

Franconian Method

The Franconian method, as described by Franz Cassian, is a single step decoction mash. The malt to wort ratio (by weight) is 1:6 to 1:7. Hot water of 80 to 85 °C is thoroughly mixed with the malt to reach about 60 to 65 °C and then rested until all hard matter has sunk to the bottom of the mash tun. Then, all the wort is drawn off and brought to a boil. All hot break is thoroughly removed, and the wort is boiled for 45 minutes. After that, it is mixed back into the mash to bring it up to 75 °C, and then thoroughly stirred and rested for an hour to continue conversion. Then a small amount of wort, about one tenth of the whole volume, is drawn off and used to boil the hops for about 30 minutes, then the rest of the wort is drawn off, added to the wort and hops, and boiled even longer (the author doesn’t specify how long, though).

Both beers brewed after the Augsburg and the Franconian method are sparged, but the resulting second runnings aren’t added to the first runnings, but rather made into a small beer called “Hansle” (if you’ve read my book, other sources also call this “Heinzele”).

Viennese Method

According to the author, this method may actually be used to produce more beer than with the Munich method, as it has been in use not only in Austria and Germany, but also in France, Norway, Russia, as well as breweries in North and South America. The method is described in very specific numbers:

To produce 100 liters of beer, 20 to 22 kg of malt are used. The total water amount is 200 liters, split up into the mash water (125 to 166 liters) and the sparge water (34 to 75 liters).

To malt is doughed in with 2/3 of the cold mash water, while 1/3 of the mash water is brought to a boil. It is stirred until it is completely smooth, and only then the boiling water is added to bring the mash to a temperature of 36 to 38 °C. The rest of the mash is done in a triple decoction fashion, with two thick decoctions and a thin decoction.

The first decoction is heated up, but not immediately brought to a boil: instead, it is rested at 70 to 75 °C for 10 to 35 minutes. After that, it is quickly brought to a boil, and boiled for 5 to 15 minutes. The boiling mash is then mixed back while thoroughly stirring to bring it to a temperature of 45 to 50 °C. After a rest of a few minutes, another third of the mash, again a thick mash, is drawn off and boiled for 20 to 50 minutes. It is then again mixed back. Unfortunately, the author doesn’t mention the expected temperature, but we can guess it to be in the range of 60 to 65 °C. For the final decoction, a larger amount of the whole mash, 40 to 50 %, is drawn off and brought to a boil so that the protein coagulates and the hot break settles. It is then mixed back into the main mash which should then have a temperature of about 75 °C. After some more stirring, the mash process is considered finished.

The mash is then lautered and sparged, and the wort is boiled with the hops. The stronger the beer, the more hops are used. Unfortunately, it doesn’t provide any specific hopping rates. Original gravities are mentioned, though: lager beers are generally at around 13 °P, while low-gravity draught beers are at 10 °P.

Bohemian Method

The Bohemian beers at that time are characterized as less malty, but rather more hop-aromatic. With every 100 kg of malt, 700 liters of water were used: 562 liters in the mash, 188 for sparging. 435 liters of water are used for doughing in at a temperature of 40 °C in winter, or 30 °C in summer. After doughing in is completed, 108 liters of boiling water are added to raise temperature. After a few minutes of rest, about one quarter of the thick mash are removed and very slowly heated up to 55 to 60 °C so that the enzymes can convert starches into sugar. After that, the decoction is brought to a boil, while the hot break gets skimmed. After 30 minutes of mashing, it is mixed back into the main mash, and stirred thoroughly to ensure a consistent temperature throughout the mash. After that, a second and third decoction are drawn and conducted exactly like the first thick decoction. After the third decoction has been mixed back, the overall temperature of the mash should be at 70 to 75 °C, and the mash is rested.

Wort is then drawn off until it is clear. The turbid part of the wort is boiled together with about 19 liters of water for a few minutes, and poured back into the mash. The mash is then moved to the lauter tan, and lautered and sparged with the sparge water that was set aside. The resulting wort is boiled with relatively large amounts of hops. Some of the hops are kept back and only added at the end of the boil to increase the amount of volatile hop aromas. This is what the author considered to be very specific for Bohemian beers and what gives them their typical hoppy aroma and flavour.

Discussion

While I’ve been working with lots of different sources when I was writing my book about historic German and Austrian beers, finding such a detailed description and comparison of various types of decoction mashing was quite refreshing. The Old Bavarian method is closest to what I’ve seen in plenty of other sources. I would describe it as the most classic method, pretty much fully based on manual labour, and done with an approach that employs volume measurements so that when done properly, no temperature measurements would be necessary. The ratio of malt to water is crazy high, though. For decoction brewing, today’s literature recommends ratios of 1:4 to 1:5. The text is not totally clear in all details, and might mean the total amount of water needed for the brew, i.e. including sparge water.

The Augsburg method, “Satz brauen” is truly odd. I’ve actually seen several different ways of how this is done, and the description as summarized above is actually the clearest one I’ve seen so far. It is possible to see why this method works and how it gets all starch converted, but it seems horribly inefficient, even in comparison to classic decoction mashing.

The Franconian method is closest to modern brewing. Any lower temperatures are skipped, and the main temperature is right at saccharification temperature. Other descriptions of the method that I’ve read don’t even employ a final thin decoction, but this might probably just be a local historic Bamberg variation.

The Viennese method on the other hand can be considered to be very modern: the specific method of resting the first decoction at about 70 °C for a while to let starches convert before the diastatic power is destroyed in the boil is a technique that even modern literature recommends, e.g. Narziß, though his recommended temperature is closer to 65 °C. And that’s what differentiates it from the classic Bavarian method: while it follows the same general pattern, it is more intricate, more detailed, more informed. It is built on top of the information that enzymes (though the book only says “diastase” without knowing what exactly enzymes are) break down starches to sugars at certain temperatures, and in the Viennese method, this is used to maximize fermentability of the wort. It is what I would call a modern method, this modernity would also be a good explanation for its success that is indicated by the author’s comment how internationally widespread the Viennese method has become.

The Bohemian method does seem a little bit more rustic, and differentiates itself by only using thick decoctions. It already builds upon the knowledge that starch conversion happens at certain temperatures, and leverages this knowledge to facilitate conversion when heating up individual decoctions. The specific mention of certain amounts of water does show that this has been thought through more and indicates that it closely follows a tried and tested recipe.

While not strictly related to the mash, the author discusses what distinguished Bohemian beers from other lager beers: the pale colour as well as the unique hopping method. I am not surprised that the author points out the use of late hopping techniques to introduce a brighter and more intense hop aroma. While we nowadays know that it’s the way of producing hop-aromatic beers, it is not a technique commonly seen in old brewing literature, where hops were only added for their preservative qualities as well as their bitterness.

All in all, this historic comparison of various mashing techniques from Bavaria, Bohemia and Austria was a great find. It gives a good insight into the shift from brewing as a craft involving manual labour (Old Bavarian method) to the industrialization of beer production supported by automation (New Munich method) and scientific methods (Viennese method). It also gives a good explanation what made Bohemian beer so unique and special in the late 19th century, which was also a reason why pale lager beers became the most widespread and successful type of beer in the world. And last but not least, it is also a good lesson for homebrewers how the decoction mashing process can be varied, in a form that’s even usable on a relatively small scale.

If you’re a homebrewer and you’ve never done a decoction: try it out. It may seem scary, but after brewing several beers with decoction mashing, I can safely say that it’s really hard to screw things up if you just follow the principle of doughing in, heating it up to about 40 °C, and then repeatedly taking out roughly a third of the mash, boiling it, and mixing it back. The mash goes through saccharification temperatures multiple times, and especially with enzyme-rich, “hot” malt that we have available nowadays, most of the conversion happens fast. I am a proponent of decoction mashing, because conceptually, it is really hard to screw up.