Tag Archives: decoction

The Story of East-German “Motorist’s Beer”

Alcohol-free beers are a hot topic these days, both because of consumer demand and improvements in quality of this beer achieved through research.

When recently talking about the subject with my friend Ben, I brought up Aubi, the East-German “Autofahrerbier” (lit. “motorist’s beer”). When looking into the topic of Aubi more closely, I found out more about its history that I’d like to share here.

First the plain facts: in the GDR, beer brewing was guided by TGL 7764, an industry standard that defined which beer types could be brewed, how they could be brewed, which ingredients could be used for them, and under which parameters each of these types had to fall. In short, it was an early form of a beer style guideline, but specifically for the East-German brewing industry.

In the 1980 revision of TGL 7764, Aubi was listed as the only alcohol-free type of beer. In its production, at most 11 kg of brewing malt per hectolitre of sellable beer could be used, and at most 9 g of hop bittering compounds (i.e. alpha acid) per hectolitre. At most 70% of hop bittering compounds could be from hop extracts. It had to be matured for at least 3 days, with a recommended time of 6 days. Its original gravity was between 6.9 and 7.4 °P, its apparent attenuation 30 to 40%, its CO2 content at least 0.38% (i.e. 3.8g/l), and its bitterness 22 to 34 IBU. In terms of colour, it had to be about as pale as pale lager beer (I can’t translate the GDR colour scales to modern ones like SRM or EBC). In bottles, it had to last at least 90 days, the longest best-before dating of all beer types (together with the Pilsner Spezial type). And unlike most other GDR beer types, it had no specific beer label colour prescribed.

The development of the beer itself was a relatively surprising one: at the time, brewmaster Ulrich Wappler at VEB Engelhardt brewery in Berlin had an unexpected surplus capacity, as the Schultheiss brewery on Schönhauser Allee in Berlin was shut down and Wappler’s technicians managed to transfer tanks to his own brewery. In East Germany, the blood alcohol limit was at 0.0 since 1956, much stricter than other Western countries at the time. Truck drivers coming in from West Germany would bring their own, specifically Birell, a Swiss brand developed and brewed at Hürlimann, and at the time (as far as I could find out) the only alcohol-free beer on the German market (Clausthaler, the later dominant alcohol-free beer brand in West Germany, only launched in 1979). Birell was even specifically advertised near the border on the West-German side with the fact of the strict alcohol ban for drivers in East Germany.

The brewmasters in East Berlin were approached whether they would be able to develop a GDR-brewed alcohol-free beer. With the free capacity, Wappler would have been able to do it and agreed to it. His problem was rather finding a way how to brew an alcohol-free beer. In the GDR, he unfortunately had no access to Western brewing literature, nor any of the Western patents, and he wasn’t allowed to get in touch with West-German brewers either as he wasn’t a party member and his brothers had left the GDR for the West. He eventually managed to get access to Western patents through a source, and studied them for 6 months. Of the two methods of producing alcohol-free beer (biological, i.e. restricted fermentation, and mechanical, i.e. physical dealcoholisation), they decided that they could build the equipment to brew using restricted fermentation.

This was still not without problems: they did not have any special yeast, so a special apparatus to quickly chill down the beer that had only just started fermenting had to be built. Then higher-ups had heard about the efforts and the supposed progress, and basically forced them to send out unfinished beer that had not fully matured, which was actually well-received.

An area where this new beer was particularly successful were the heavy industries, in particular glass blowers and steel mills. In these jobs, workers were of the opinion that they needed to drink beer to help with salivating. They refused to just drink water, while at the same time, the union had strictly banned alcohol. So they tested the alcohol-free beer (at less than 0.5% ABV) in some of these factories, and the workers liked it. Also price-wise, at 75 Pfennig per bottle it was cheaper to buy than imported Birell, and also cheaper than other domestic beers. So their alcohol-free beer filled a gap, even more so in the heavy industries than for motorists. It took some tweaking of the recipe, including hop oils, to make it a really good beer, and in the end, the product also piqued the interest of other countries of the Eastern Bloc like Bulgaria and Czechoslovakia, who also tried to brew similar beer but all had over 1% ABV and none of them tasted nice.

The cheap domestic price of just 75 Pfennig also became a problem in terms of economics: while it required fewer ingredients, brewing Aubi was much more energy-intense, because mashing involved a special mashing schedule (more on that later) and restricted fermentation required more energy on top of that for chilling down the beer. Because of this, production volumes were lowered.

The beer itself was brewing like this: the grist contained 20 to 50% (sic!) unmalted adjuncts and was mashed using a special type of decoction mashing that specifically skipped the optimal temperatures of beta amylase and rather inactivated them to then have alpha amylase saccharify the starches, resulting in a much less fermentable wort. After only briefly starting fermentation, the wort was chilled down quickly to restrict fermentation.

Internationally, the East German alcohol-free beer was also a success, and was exported from 1986 to the United States under the brand name “Foxy light”. If we can believe a tasting and ranking of alcohol-free beers in the Chicago Tribune from 1988, Foxy light couldn’t exactly compete in terms of flavour with other European imported alcohol-free beers at the time, but fared well compared to domestic alcohol-free beers, while also being one of the cheapest ones. In England, the same beer was sold under the brand “Berolina”.

With the end of the GDR, production of Aubi also ceased. Most East-German breweries were shut down as they were completely outdated compared to their West German counterparts. Brewmaster Wappler managed to get work in West Berlin breweries for his workers. Until his retirement, he helped conceptualising brew systems for other breweries and training people on them.

Sources:

Interpreting a 1960s Bavarian Dunkel Recipe

Whenever somebody asks me how I would brew a Bavarian Dunkel, I have to respond that I never actually brewed one on my own. Instead, I rather point to an authentic modern-ish recipe from a Bavarian brewery from the 1960s.

A few years ago, Urban Chestnut Brewery from St. Louis, MO posted a sheet from 1967 brewing records of Brauerei Erharting in Bavaria. Their brewmaster, Florian Kuplent, had originally apprenticed there, and most likely got his hands on these records that way.

The recipe is interesting because there are a lot of assumptions baked into it that you’d only know if you had an idea about Bavarian brewing. It also challenges conventional wisdom that Bavarian brewers would just brew their Dunkel from 100% Munich malt. At least in the 1960s, this was not true anymore for this recipe.

This recipe for Export Dunkel starts with the grist: it simply says 1350 kg of malt, of that 50 kg pale malt (lit. “Hellmalz”), 50 kg CaraMunich (originally CaraMünch, the German brand name), 10 kg roasted malt (Farbmalz in the original). What the recipe doesn’t say is the rest. The use of Munich malt (likely on the darker side) was simply implied from the type of beer that was being brewed. The pale malt was most likely a Pilsner malt. That way, we end up with a grist like that:

  • 1240 kg Munich malt (91.9%)
  • 50 kg Pilsner malt (3.7%)
  • 50 kg CaraMunich malt (3.7%)
  • 10 kg roasted malt, e.g. Carafa special II (0.7%)

Why the Pilsner malt? I can only speculate, but I assume that this might have been formulated under the assumption that the Munich malt had so little diastatic power that it would only self-convert and not fully convert the (enzymatically inactive) caramel and roasted malts.

The next part is the mash. It starts with doughing in the malt and letting it sit for 20 minutes at 35°C. This was typically done to ensure that all the malt was fully hydrated. Nowadays, this would be ensured through a pre-masher that would combine water and malt just before it goes into the mash tun.

Then, the mash was heated up to 52°C within 15 minutes. The mash tun must have been heatable.

The recipe then further mentions to mashes. For the first mash, 22.5 hl of mash were pumped into the kettle while the stirrer was running. In the kettle, the mash the underwent a multi-step mash on its own: 10 minutes protein rest at 52°C while a bit of wort was drawn off (Malzauszug) and kept in the Grant, 10 minutes saccharification at 60°C, 10 minutes saccharification at 65°C, 70°C until iodine test was negative and the mash was fully converted (normally 20 to 25 minutes) and then 75°C for another 5 minutes.

This step mash prior to boiling the mash is done to maximize the use of the enzymes that will eventually be destroyed, and to convert as much starch as possible, so that the intense boil will only extract some more starches to be converted in the second mash.

Then the mash was brought to a boil, boiled for 35 minutes and then mixed back into the main mash which then reached a temperature of 65°C.

Then the second mash started: 23 to 23.5 hl of mash were again pumped into the kettle, rested for 10 minutes at 65°C, then again rested at 70°C until iodine test was negative, and then 10 minutes more at 75°C. It was then boiled for 25 minutes, and mixed back into the main mash to reach a temperature of 74°C.

The wort that was drawn off must have then been mixed back in, the recipe is not fully clear on this, though. I don’t know exactly why, but I assume that this was done to retain some amylase enzymes and ensure that some end up in the mash just before lautering to help convert any last few bits of starch (even though this is unlikely given how thorough the extraction must have been through 2 long decoction boils).

Then lauter and sparging happened to collect about 100 hl of sweet wort which was then boiled for 2.5 hours. The resulting amount of wort at the end would have been 78 to 79 hl with an OG of 12.7 to 12.8 °P.

The hopping schedule looked like this:

  • beginning of the boil: 4 kg Hallertauer hops
  • 1 hour after beginning of the boil: 4 kg Hallertauer hops
  • 45 minutes before the wort is pumped off the kettle: 3 kg Spalter hops

The last one is particularly important: the timing does not depend on the end of the boil, but rather on when the wort is moved from the kettle to the chillers. None of the hop additions come with any indication of alpha acid content. There is one source though where we can get an estimation: international hop trader Barth Haas has its full range of historic hop reports online, both in German and English. The 1966-1967 report in English at least reports the “bitter value Wöllner” for some hops: 6.2 for Hallertauer hops and 6.6 for Spalter hops, both from the 1966 crop.

This “bitter value Wöllmer” was an early approach to estimate the bittering quality of hops. In particular, this value is calculate as alpha acid % + beta acid % / 9. For both Hallertauer and Spalter hops, we can assume that the alpha acid content is roughly the same as the beta acid content.

6.1 = x + x / 9 and solving for x gets us an alpha acid content of about 5.5% for Hallertauer hops.

6.6 = x + x / 9 and solving for x gets us an alpha acid content of about 5.9% for Spalter hops.

Bear in mind that these are just estimations, but should nevertheless give us a general idea about whether these were more high or low alpha acid for the variety.

And this is how you interpret a 1960s German recipe for Bavarian Dunkel.

Double-Decoction Mashing on a Home-Brew System Not Designed For Decoction: A Post-Mortem

Today, I brewed together with Ben Palmer at the MASH PIT, a kind of nanobrewery/home-brewing co-working space that allows you to brew your own beer on the brew kits installed there. Ben had recently moved to Berlin, and since we knew each other through Twitter, we met up and eventually decided to brew a beer together.

One thing that I’ve been wanting to do for a long time at the MASH PIT was to brew a beer using a decoction mash. Ben was also happy to do that, so we agreed on a simple recipe. Our grist consisted of 98% Pilsner malt and 2% CaraMunich II, while the hops we chose were Celeia (Ben had never used Slovenian hops, and since I hadn’t either, I was happy to also try them out). The original idea was to ferment it with a Kölsch yeast, but since we were informed that the MASH PIT had run out of that yeast the day before the brew day, so we substituted it with Nottingham Ale yeast instead, another fairly neutral and attenuative top-fermenting yeast. For mashing, we wanted to do a double decoction, for several reasons: my reasons were that I wanted to try brewing a double-decocted beer on the MASH PIT kit, and I also wanted to try brewing an ale of some sorts that had a distinct decoction character. This was something I had stuck in my head ever since my last visit to Prague, where I tried a few ales [sic!] from Pivovar Matuška, and they all had a distinct “Czech” flavour that I could only attribute to decoction mashing. Ben’s reason to try out double decoction was that he hadn’t really much experience beyond a few demonstrations at his vocational school.

A few words on the MASH PIT brew kit: it is fairly simple and straight-forward. It consists of three large pots of maybe 75 litres volume (the scale only goes to 65), all equipped with taps on the bottom and the top and embedded thermometers. One of these pots is sat on a gas burner and mainly serves as kettle to boil the wort as well as to heat up the liquor (brewing water). The middle pot serves as mash and lauter tun and is equipped with a removable false bottom. It also comes with a RIMS attachment that allows you to pump wort (a liquid pump is part of the setup) from the false bottom through the attachment and sprinkle it again on top of the mash. The attachment has a heating element that can be turned off and on. With this setup, you can do a multi-step infusion mash fairly easily. The third pot is also equipped with an electric heating element and mainly serves as hot liquor tank (HLT). Through three switches, you can turn on and off pump, RIMS heating element and HLT heating element.

But instead of following this scheme, we instead decided to repurpose the kit for decoction mashing. With about 11 kg of grist, we filled the mash tun with 44 l of liquor at 45°C, then mashed in. This increased the overall mash volume to 55 l. The mash temperature was 41°C. After a short rest, we pulled 36 l (i.e. two thirds) of thick decoction and moved it over to the kettle. We brought the decoction up to a temperature of 70°C, which went very quickly thanks to the powerful burner. A quick rest of 15 minutes to at least partially convert the available starch, and then brought the mash up to a boil. That’s where the problems started: we had a bit of a boil-over, which was our mistake as we partially covered the pot with the lid and also kept it unwatched. After a quick cleanup and making sure we hadn’t lost much of our decoction, we continued boiling it for another 10 minutes.

A watched pot never boils, an unwatched pot boils over.

We then started mixing the decoction back into the main mash. We noticed that even though we had moved only about 50% of the decoction, we were already overshooting our target temperature of 65°C. That was not good. We had to improvise somehow, and so we decided to add some more cold water to the decoction to bring its temperature down. We eventually got that done and ended up with a mash at pretty much exactly 65°C, but now with a total volume of more than 60 litres, which we left to rest for 50 minutes.

So obviously we had overdone it with the decoction volume. I had chosen two thirds as the initial volume because that’s what had worked for me at home on my home-brew kit. Except my kit at home is for 20 litre batches, while this system is for 50 litre batches. I realize that my home system is at such a small scale that boiled mash can cool down fairly quickly, but I didn’t think that effect would effectively disappear at at scale-up from 20 to 50 litres.

The change in mash volume also meant that any previous estimations of the volume for the second decoction were out the window. We then decided to just estimate it to one third of the total volume, and then a bit, so the second decoction we pulled was thin and sized at 25 litres.

We brought this second decoction again to a boil, boiled it for 5 minutes, and then mixed it back again. By that time, the main mash had cooled down to 61°C, so the final temperature after mixing back was only 71°C. Not exactly the 75°C where we wanted to get to, but still good enough. We then left the mash to rest for another 30 minutes and prepared for lautering and sparging: we cleaned the kettle, filled up the HLT and heated the sparging liquor.

With everything prepared, we decided to just skip the iodine rest (YOLO, right?) and started a vorlauf. We only got very few hard bits and very quickly got a very clear wort. We then connected the mash/lauter tun’s tap to the kettle, and slightly opened the tap. Lautering went quickly and ran off smoothly, looking very clear and bright. We then started sparging by pumping liquor from the HLT onto the mash, breaking up the stream with a highly technical piece of equipment: the mash paddle.

Kettle in the front, sparging action in the back

We managed to collect a total of 63 litres of sweet wort. In the end, this was limited by gravity: at 63 litres, the level of the wort was the same as the tap of the mash/lauter tun. We then starting bringing the wort to a boil.

Ben then had the idea that we should check the gravity of the last runnings with the refacrometer that we had used to check on gravities during the process. Turned out, the “last” runnings still were at more than 5°Brix. Instead of just conceding to the laws of gravity, we should have lautered the last remains into a separate vessel and topped off the kettle instead. It probably would have also helped with another issue we noticed: according to the refractometer, the pre-boil gravity was at 12.4°Brix. Our plan was to have an OG of 11.8°P (°P and °Brix are very similar scales, and virtually identical and practically interchangeable). So strangely, we seemed to have a much higher OG to expect than what we had planned and calculated. Of course, we didn’t know what extract efficiency to expect on this home-brew kit, but still.

We decided to continue with boiling the wort anyway, and added hop additions at 90 minutes and 5 minutes before flame-out, and then more during whirlpool. Post-boil gravity according to the refractometer was at 15°Brix. This was way too much, and would have meant a much greater efficiency than what we could have planned for.

We then sent the hot wort through the plate chiller to the fermenter at a nice 18°C, and measured the OG using a saccharometer. It really was at 14.1°P. This was weird, a difference of almost one degree. I then rechecked the refractometer with just water, and it turned out that refractometer wasn’t properly calibrated.

Another problem also popped up when pumping the wort from the kettle through the plate chiller to the fermenter: towards the end, we started pulling in hot break and hop particles. We were then told that they actually had a hop filter that we should have attached that would have allowed us to get more of the wort from the kettle to the fermenter without sucking up any of the gunk. We had to stop the pump early, and only ended up with about 45 litres of wort, but at a higher OG than we what we wanted.

Our solution to that was simple but almost embarrassing: we decided to dilute the wort with cold water to bring the OG down to 12°P. The final step was then to hydrate the yeast (3 sachets of Nottingham Ale yeast should do just fine) with some fresh wort, pitch it, and move the fermenter to the temperature-controlled fermentation room.

The day was concluded with lots of cleaning up and a glass of cold, fresh beer from the MASH PIT tap room. A lot of things went wrong during the brew day, but we managed to salvage any issues, and still arrived at something that I think should come out pretty nicely. I’m definitely looking forward to trying out the resulting beer. The main things I want to see is whether I really do get a pronounced decoction character in the beer, and of course, what Celeia hops taste like in a beer.

A brewing selfie. We were smiling under these masks, I swear.

Mahrs aU Clone, Iteration 1

As I’ve announced a month ago, my homebrewing project for 2020 is to develop a clone recipe for Mahrs aU. I brewed the first iteration on December 27, and here’s a quick report on how that went:

My grist was fairly simple, 2.4 kg Pilsner malt and 2.4 kg Munich I malt, both from Weyermann. I doughed in with 20 litres of water which I had treated with 6 ml of lactic acid (something something counteract local water’s hardness, I calculated this ages ago and stuck to it since, I’m terrible with water chemistry). I then conducted my preferred double decoction mash where I start with a very large thick decoction, rest it at around 70°C when heating up, then boil it and mix it back, and then pull a thin decoction, boil it, and mix it back again. The temperature steps the main mash was undergoing in this case were 39°C (dough-in temperature), 62°C and 72°C. I then moved the mash to the lauter tun, recirculated to get clear wort and then started lautering, measuring 17.6 Brix on the first runnings. I continuously sparge, and after 30 minutes, I had enough wort collected to bring it to a boil. Pre-boil gravity as determined by refractometer was 11 Brix.

After 90 minute boil, with hop additions (2019 harvest Perle, 7.2% alpha acid) at 90 minutes (32g) and 10 minutes (10g) before the end of the boil, I moved the wort the a fermenter and chilled it down to 10°C before adding two rehydrated sachets of W-34/70 yeast. Fermentation took off about 36 hours after pitching the yeast.

Things didn’t go quite as planned, as the wort’s OG turned out to be 13.3°P. My grist calculation was based on previous batches in which I employed the same mashing regime, but this time, for whatever reason, efficiency was quite a bit better than what I wanted to achieve. I’m not going to complain about it, as it’s only 0.6°P (roughly 0.002 in gravity points) higher than where I wanted to get to.

Fermentation was quite a bit slower than usual. I’m not sure why, but I may have rehydrated the dry yeast improperly, therefore slightly underpitching. Even after four weeks, fermentation did not seem quite finished. I would have waited, but two days ago, another problem came up: the seal on the fermenter’s tap was leaking. Not a whole lot, but in the tray underneath, a few hundred ml of beer had built up. Since this was just the first iteration, and things weren’t 100% right from the beginning, I decided for an emergency plan: instead of lagering properly, I just cold-crashed the beer, hoping not more would leak between Friday and today, and then bottled the beer today. With 4.4°P, I’m not 100% sure the beer had completely finished fermenting (though there wasn’t really much of a noticeable residual sweetness), but I bottled it anyway and just let it naturally carbonate over the next few weeks. To be frank, I’m not particularly happy with that, but given that things weren’t right from the beginning, it’s still an acceptable shortcut for a first iteration.

A quick taste test directly from the fermenter revealed that the beer indeed tasted remarkably close to the original Mahrs aU. While the beer was pretty clean-tasting, the hop bitterness still seemed a bit rough. My concern is that whenever this has aged a bit and smoothed out, the bitterness might not be quite high enough. Bear in mind that I based the hop additions and overall bitterness just on some very flimsy circumstantial evidence. Since then, I’ve received multiple pointers to other sources talking about the Mahrs aU parameters, such as this very helpful comment by DB who mentioned that Michael Jackson had written about aU in 1999, when it was still bittered with Northern Brewer and Hallertauer Tradition to 36 IBU, and this reply on Twitter pointing out that Ron Pattinson’s book Decoction! (seriously, you should buy it) contains OG, ABV, real extract, apparent attenuation, colour and bitterness from the year 2000 for “Mahr’s Bräu ungespundet – hefetrüb” (aka Mahrs aU), setting the bitterness at a whopping 42.5 EBU.

I’m still waiting for the bottled beer to condition and slightly mature before I’ll start a proper taste test the results of which will then be the basis for my next step. Based on the brew day itself, I will probably slightly reduce the amount of malt the next time so that I can get closer to 12.7°P in OG than the 13.3°P of the first iteration. Also depending on how the bitterness shines through, I may slightly increase the bittering hops.

I also chucked out that particular fermenter and ordered myself a 30 litre Speidel fermenter instead.

#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.

19th Century Brewing Methods in Germany and Austria

Only the other day, I stumbled upon a book called “The Art of Brewing“, written by one David Booth, published in 1834. It has a whole section of brewing in foreign countries, discussing differences in brewing between Munich, Prague, Vienna, and other cities. The basis for this section is credited to two unnamed guys, can you guess who?

For the greater portion of ” the Brewing in Foreign Countries,” I am indebted to the manuscript and oral communications of two German Brewers (from Vienna and Munich), who have been, and now are, visiting the principal towns of Europe, for the laudable purpose of acquiring information concerning their business.

Yep, that sounds very much like Gregor Sedlmayr and Anton Dreher.

I also found another book, “Vollständige Braukunde” by Johann C. Leuchs,  that discusses the brewing methods of various German cities. In this article, I will try to summarize and discuss different German brewing techniques from the 19th century, and how they would be seen from a modern (home)brewer’s point of view.

Munich

For the mash, a mash tun made out of copper, with a false bottom, and a second, smaller copper, were used. The second copper was used for boiling the mash. The standard recipe is described to be 8 quarters of malt and 60 pounds of best Bavarian or Bohemian hops to produce 27 barrels of keeping beer. Calculating what the outcome of that would be, that would be a beer with about 6 to 7.5 % ABV, with probably 35 to 50 IBU. It does mention the Munich beer as keeping beer, meaning it was matured, or lagered, for a relatively long time.

The coarsely ground malt is doughed in, while the small copper is used to bring liquor to a boil. The boiling liquor is then added to the mash, to result in a 40 °C mash. Then a decoction is drawn, and brought to a boil. The author mentions a thick froth that is beaten down back into the mash. I assume this is hot break, and nowadays you would rather skim the scum instead of beating it back into the mash.

The first boil takes about an hour, where it gets a darker colour, until it is put back into the mash, to raise the temperature to 55 °C. Immediately, another decoction is drawn, but only boiled for 30 minutes, and then put back, with a resulting temperature of 67 °C. A third, thin decoction is then drawn, both taken from the top and taken from the tap (the mash tun has a false bottom, after all). Then it is boiled for 15 minutes, and put back, to reach a temperature of 75 °C. That whole procedure takes about 5 hours.

After that, the wort is drawn off. Hops are added while the first runnings are still drawn off, so this constitutes a first wort hopping. The overall boil lasts 2.5 to 3 hours. Fermentation is bottom-fermenting, as expected. What’s interesting is that after primary fermentation, the young beer is drawn into casks. A batch is spread out over lots of casks, though, so it takes about ten batches to properly fill all the casks. I presume this is to blend all the batches and to end up with a very consistent product over all casks even when the individual batches differ. Lagering period in the cellar is mentioned as lasting eight to ten months. That is indeed a keeping beer.

Beer brewed for the winter differs from this, as less hops are used, more wort is drawn off, and it’s boiled for a shorter period of time. There is very little maturation, and secondary fermentation for carbonation is initiated with Kräusen, and essentially happens in the publican’s cellar. This very much sounds like a running beer. Comparing with modern drinking habits, this is very counter-intuitive, as you’d expect the lighter beer to be brewed for the summer as a refresher, and the bigger beer to be made as a warming, boozy drink.

Augsburg

Apparently, the brewing methods in Augsburg were quite different from the rest of Bavaria. It starts with the malt: it is ground finely. The boiled hops of the previous batch are put on the false bottom prior to putting malt and then cold liquor over it. This is left for six hours. Boiling liquor is then added, and mashed for half an hour, and then more hot liquor is added, to bring it to 60 °C. This is then left for two hours. Sweet wort is then drawn off and put into the cooler. More hot liquor is added, and mashed for half an hour, with the resulting temperature being 67 °C. Then “all the goods” (I presume this means all hard matter) are put into the copper with hot liquor, and boiled for 45 minutes, then put back into the thin mash. The resulting mash is then at 86 °C. After some time, the cooled wort is put into the copper, the wort from the mash is also drawn off, hops are added, and the whole thing is boiled for two hours.

Fermentation is bottom-fermenting, and the beer is ready after about 2 months of maturation. Usually though, it is kept in large vats for a year to 1.5 years.

According to “Vollständige Braukunde”, beer brewed like that requires more cleanliness than the Munich approach, but has a higher yield and produces a milder beer.

Overall, a rather weird method in today’s standards. It seems like an infusion mash in the beginning, but with a final decoction, which would extract complex carbon hydrates, but leave the mash at temperatures where all amylases would have already been denatured, and no enzymes would be left to convert the starches into more simple sugars. Did the Augsburgers like their Blausud? (a Blausud is when a wort sample, mixed with an iodine solution, turns dark blue: it is an indicator that there’s still unconverted starches in the wort)

Prague

Prague’s brewing methods are described as similar to Munich, but with a fermentation “of the opposite kind”, which I assume means that in the 1830’s, Prague was still brewing with top-fermenting yeast.

Dough in starts at 46 to 50 °C, with an initial rest of nearly an hour. During that mash, more hot water is added to reach 59 to 63 °C. Then a decoction is drawn, brought to a brief boil, and then put back to get up to 67 to 68 °C. Then another rest of an hour follows. Wort is then run off, a Vorlauf if you will, with the express purpose to get rid of any grains underneath the false bottom. This wort is brought to a boil, and put back, to bring the temperature of the mash to about 84 °C. It is also emphasized that the grains must not be disturbed. Then a small portion of the wort drawn before is brought to a boil together with the hops, and the hops are taken out after 45 minutes. In total, the wort seems to get drawn off in batches and boiled, with the hops getting reused. A sparge is done, and the runnings are boiled with the hops from the previous boils.

Fermentation is done at 20 to 22 °C, so obviously top-fermenting. Maturation then happens in ice-cooled vaults for four to six weeks, and is served directly out of that cold environment. Yep, ice-cold beer.

Anyway, what we can see here is that the Munich style of mashing is a triple decoction, while Prague employed a double decoction.

Vienna

The crushed malt is doughed in with cold water, and mashed for two to four hours. Then cold wort is drawn off, and is brought to a boil together with liquor, boiling for 45 minutes. The froth on the top is skimmed off. It is then put back onto the malt, with a resulting temperature of 40 °C. Now this seems quite odd to me, as it would mean that a lot of the enzymes in the wort would be denatured quite early on.

Then something truly odd is done: wort is drawn off, and pumped back onto the mash. This is done for over an hour. A certain amount is kept in the copper, and again brought to a boil, but as soon as it starts boiling, it is added back to the rest of the mash, to increase temperature to 57 °C. Then more wort is drawn into the copper, again brought to a boil, boiled for 30 minutes, then put back into the mash. This is now left for 30 minutes at 72 °C. And then more wort is drawn off, again brought to a boil of 45 minutes, put back into the wort, and left for another hour at 82 °C.

Then wort is drawn off once more, and hops are added. When all the wort has been drawn off, the grains are loosened, and water of 56 °C is sprinkled onto it. The wort is boiled for 75 minutes, and some of it is put into the cooler. Then the second runnings are drawn into the copper, and boiled for another 90 minutes.

Then the wort is cooled to about 30 °C, and yeast is added. That’s a crazy pitching temperature. Fermentation is vigorous, and the young beer that is thrown out during the fermentation is collected and fermented in a separate vessel. This sound vaguely like the idea of a Burton Union, although with a separate vessel instead of recirculation. Shortly after fermentation has finished and the yeast has settled, casks of the young beer are sent out to the publicans. This all happens within 3 days.

So, in total, quite a strange process. Kinda like a decoction, except only thin decoctions are drawn. I wonder what prevented this from resulting in a Blausud, as well.

Berlin

This gets interesting now. Berliner Weisse. “The Art of Brewing” describes it as a beer made from 5 parts of wheat malt and 1 part of barley malt. That’s quite different from the 2:1 or 1:1 recipes that are listed in other old publications. “Vollständige Braukunde” mentions 20 parts of barley malt, 10 parts of wheat malt, and 2 parts of oat malt.

The finely ground malt is doughed in, and hot liquor is added to bring the temperature up 52 °C. This is left for an hour. Then wort is drawn off, and boiled with hops for 15 minutes. A thin decoction is drawn to interrupt the boil, and when this has reached 93 °C, it is put back into the mash, and left for 30 minutes, with a resulting temperature of 67 °C. Then another thin decoction is drawn, heated up to 96 °C, then both the mash and the decoction are put into the “tap-tun”, what sounds like a lautering vessel with a false bottom which is covered with straw (some sources say straw used in lautering was previously boiled in water). The resulting temperature in this tun is 75 °C. The wort is then drawn off, very slowly, though, and hot liquor is used for sparging. The overall lauter and sparge takes 7 hours, to produce a very clear wort. The wort is then put into the fermenting vessel, where yeast is added. Fermentation quickly begins, and the beer gets already shipped out to the publicans at this early stage.

In “Art of Brewing”, the author mentions that brewers thus have no yeast, and must buy it back from the publicans. To keep their yeast strains reasonably clean, they preferably buy from publicans that deal with other breweries than their own. The publicans also take care of bottling and storing the beer until it’s drinkable, which is usually after 14 days.

In total, this is quite the interesting process, as it does a kind of decoction, with the hop boil during the mash, and no further boil. Berliner Weisse is often described as a no-boil recipe, and people often ask themselves how the hops are added to it if there is no boil: directly during the mash. This way, the amount of isomerization of the alpha acids is easily to control, which is usually not the case if you added hops to a thicker mash that would undergo several decoctions.

Summary

In this article, I tried to summarize descriptions of different brewing techniques in German and Austrian cities at that time, in particular Munich, Augsburg, Prague, Vienna, and Berlin. It is interesting to see how the approaches completely differ, in particular the amount of decoctions that are drawn, what kind of decoctions are drawn, what is boiled for how long and in what order, and what temperatures are kept. With today’s knowledge and understanding of brewing and the microbiology behind it, it is fascinating to see what would be considered good practice nowadays, and what wouldn’t. The Munich triple decoction is a well-researched and well-documented method, as is the Prague double decoction. You would find descriptions of these in most modern brewing literature. The other methods, not so much. There, we find temperatures that would extract more tannins, or early thin decoctions that would denature lots of crucial enzymes early on in the brewing process. I seriously wonder how these brews went fine, and whether they produced Blausude.