Tag Archives: vienna lager

Decoding the Colour of Historic Vienna Lager

Back in 2015, when I started looking more closely into the historic specifications of Vienna Lager, one question where I started speculating and couldn’t really get a good answer was the question of colour. I based this off historic records that I had found in one of Ron Pattinson’s books, “Decoction!“. The provided value of “6.3” (no units) seemed reasonably close to be SRM, but as Ron commented below my posting, the beer colour is not in SRM, and that he’s not sure what exactly it is.

Well, today I can proudly proclaim that I have finally discovered not only what the “6.3” means but also how the value relates the modern beer colour units like SRM or EBC.

The whole thing started with me finding the original source for the specs Ron had put in his book. In fact, I had found these specs reprinted in several other books, as well, but all of them lacked information what the colour value actually meant. The original source is an article in Dingler’s Polytechnisches Journal, “Untersuchung der Biere, die in Wien getrunken werden” [Examination of the beers that are being drunk in Vienna] by Professor Fr. Schwackhöfer, published in 1876. Underneath the rather long list of analyses (which is great because it gives us other clues; I’ll get back to that), almost at the end of the article, it briefly mentions the system that was used to determine the beer colour: a system called Stammer’sches Farbenmaß.

From what I could find out, the Stammer’sches Farbenmaß [Stammer’s colour measurement] was originally developed to grade the colour of sugars in the sugar industry. It was in use from the 1870’s to as late as the 1930’s. Quite a few similar systems like that existed. In English-speaking literature, it was often called Stammer’s colorimeter. It worked by comparing the solution to be tested(or in the case of beer, just the beer) with a standard glass plate. It consisted of two glass tubes. One tube was filled with the beer (or sugar solution), while the other one was covered with the standard glass plate. Both tubes were illuminated from the bottom, and a prism at the top allowed the user to compare how both the standard solution and the glass plate looked like. You could then lower an glass immersion rod into the solution until the colour and shade most closely matched the glass plate. The measurement of colour was then the number of millimeters you had lowered the immersion rod into your solution.

The tricky thing with Stammer’s colorimeter is that there are two values you can work with. You have the direct reading, i.e. the number of millimeters of immersion, and you have the colour value, which is 100 divided by the reading.

A more detailed description of Stammer’s colorimeter as well as other systems of that time can be found in the Handbook of Sugar Analysis by Charles Albert Browne.

The next thing I then had to find was a way of converting readings from Stammer’s colorimeter to other units. The only source I could find was the brief article “Conversion Curve for Lovibond’s Tintometer and Stammer’s Colorimeter“, published in 1914 by Carl A. Nowak in the Journal of Industrial and Engineering Chemistry. This is great, because Lovibond is a well-known scale that has historically been used to grade the colour of malt and beer, and is apparently still in use to a certain extent to grade malt colour. The article contains a chart that shows the relationship between Stammer’s colorimeter and Lovibond values.

The Y scale contains the value of Stammer’s Colorimeter, while the X scale contains the corresponding Lovibond value.

What is noticeable in the chart though is that there is an inverse relationship between these two: higher Stammer values correspond with lower Lovibond values, and vice versa. But what is the Stammer value exactly? We have two available, the reading, and its inverse, the colour value. That’s where the comprehensive list of analyses comes in handy. Not only does it contain various pale lager beers, it also contains colour values of beers that we know are most definitely dark beers, in particular Salvator with a colour value of 41.5, and a bottled Porter with a colour value of 40. So from that we know that the higher the value was, the darker the beer was.

Since the chart indicates that the lower the Stammer value in the chart, the darker the beer, we can derive that the chart contains the Stammer colour value, while the values in the analysis are the direct readings, i.e. the amount of millimeters the rod was immersed in the tested beer.

To convert the 6.3 reading to the Stammer colour value, we simply calculate 100 / 6.3 = 15.87, and look up the corresponding Lovibond value in the chart, which is about 4.6 to 4.7. In modern units, this is equivalent to 5.5-5.6 SRM, or 10.8-11 EBC.

So there we have it, the colour of historic Vienna Lager. It’s paler than the usual beer style guidelines will say about Vienna Lager, but it fits what I’ve been saying for quite a while, that historic Vienna Lager was most likely paler than its modern versions, and that the usual beer style guidelines don’t capture the historic examples.

 

The Water Profile for Vienna Lager

The last time I blogged about Vienna lager, I wrote down everything we know about the historic specifications of the beer style and how it was brewed in the last few decades of the 19th century. The only point that was speculation on my side was the water profile. I can now say that this has changed (kinda), because I found a source quantifying the chemical compounds in the brewing water of the Klein-Schwechater brewery.

By pure accident, I stumbled upon an analysis of the brewing water (well water) of the brewery in Klein-Schwechat, in the book “The Theory and Practice of the Preparation of Malt and the Fabrication of Beer, with Especial Reference to the Vienna Process of Brewing” by Julius E. Thausing. It’s actually the English translation of a German book. One problem with the analysis is that it doesn’t specify any units for most of the numbers. It does specify the amount of residue after the water has been evaporated (in grams), but that was it. Unlike the English translation, the German original at least references the original source other than just specifying the author, Lermer. The original source for this analysis is Dingler’s Polytechnisches Journal, volume 187.

This journal apparently has quite a bit of history. It was founded in 1820 by chemist Johann Gottfried Dingler, was published for 111 years, and covered all topics from agriculture, mining and metallurgy to machine construction, chemistry, geology, electrics, and many more subjects. For the history of engineering and technology, it is a great source. Fortunately, all of its volumes have been digitalized by Humboldt University in Berlin, and published online. So of course, we also have the original source of the water analysis available. You can find it here. Even though the original source is more detailed, and not only contains the water analysis of the brewing water of Klein-Schwechat but also water analysis of the old well and the river Schwechat, it is not in any way clearer regarding units than what we had in the English translation of Thausing’s book. At least we do learn that Klein-Schwechat brewery had two wells, an old one and a new one, and at the time of the article’s publishing, all brewing water was taken from the new well, which is the analysis that has been reprinted by Thausing.

So by itself, the analysis is unfortunately not really helpful. If anybody knows how to interpret the numbers, I’m grateful for any help with it.

As for the author of the analysis, Johann Karl (Carl in some sources) Lermer is quite the interesting person himself. He was hired in the 1860’s by Anton Dreher as brewery technician but apparently quickly rose the ranks and became head of Dreher’s Trieste brewery. In the Polytechnisches Journal, he published a number of articles. Given his background as conducting analyses at Dreher’s breweries, it gives an interesting insight into what were technical subjects industrial-scale lager breweries at that time were concerned about: chemical analysis of Lupulin, analysis of barley malt sprout, the issue of beerstone in pipes, the issue of mold in wooden fermenting vessels, the effects of freezing beer, malting experiments, or chemical analysis of hot break. A complete list of his contributions can be found here.

Besides the theoretical side, I’ve also been active on the practical side of Vienna lager brewing. Recently, we brewed a Vienna lager reasonably close to the historic specifications, with an OG of 13.4 °P (historical sources say 13 to 13.25 °P, the difference is due to a slighter greater mash efficiency), and 4.5 °P FG (which is close to the 4 to 4.25 °P you see in some historic sources), from 100% Vienna malt. One modification I made was the use of a double decoction mash instead of the more traditional triple decoction: I dough in at 38 to 40 °C and take a huge first decoction that brings temperature up to 65 °C. That way, the only protein rest is very briefly happening when heating up the first decoction. The second decoction then brings the temperature to 72-75 °C. That way, I skip an extensively long protein rest which wouldn’t exactly be productive with modern malts. I also deviated slightly from the hopping schedule, and only had one hop addition. I also made a slight mistake: my recipe in BeerSmith still had 3% alpha acid set for the Saazer hops, and I forgot to compensate for the 4.2% alpha acid Saazer hops that I had bought. So instead of 30 IBU, the resulting beer now has roughly 40 IBU. Oops.

Nevertheless, the outcome is nice: after 3 weeks of fermentation and many more weeks of cold lager, it’s just finished carbonating in the bottle and ready to drink. The bitterness is nicely counter-balanced with the residual sweetness coming from the low attenuation of the WLP820 lager yeast. Personally, I’m perfectly fine with the higher bitterness, even though it doesn’t 100% hit the original specs of the historic style. Even at 30 IBU, the beer would have enough bitterness to work nicely enough with sweetness. The 100% Vienna malt bring enough own malt flavour without making the beer cloying. All in all, not only a good example for the style, but also a reminder that for some beer styles, process is at least important as the careful choice of ingredients.

Vienna Lager: Another Piece of the Puzzle

In several previous postings, I wrote about various details in my effort to reconstruct historic Vienna lager as it was brewed in the 19th century by Viennese breweries, in particular Anton Dreher’s Kleinschwechater Brauerei, and exported all over Europe.

In a posting about a month ago, I discerned various mashing methods as they were described in the 1887 book “Die Dampf-Brauerei. Eine Darstellung des gesammten Brauwesens nach dem neuesten Stande des Gewerbes” by Franz Cassian. Despite all the interesting information that I was able to get out of that book, I missed one particular table much earlier in the book that shows a brief but informative overview over how Munich lager, Vienna lager, and Bohemian lager are brewed.

(click on the image to expand)

While much of this information was already known to me, there are a few more interestings bits and pieces in there: it lists a hopping rate of 1.5 kg per 100 kg of malt (which, after some calculation, should be roughly equivalent to between 3.45 g/L and 3.75 g/L). We get a hop boil time (2 hours), and a more detailed hopping schedule: 1/3 of the hops are added to the first runnings (so-called first wort hopping), while the remaining hops are added 45 minutes before the end of the boil. Unfortunately, the same book describes this just a few pages afterwards in words, and there it says that 2/3 of the hops are added 45 minutes after the beginning of the boil. At a 2 hours boil, that would be 75 minutes before the end of the boil. Personally, I find the latter a bit more convincing.

It also lists 13° as the OG of Vienna lager. Both the OG and the hopping rate corroborate previous findings from other pieces of literature. While not exactly new information, it adds much more confidence to this information.

All in all, we’ve now got the following information about historic Vienna lager:

  • Original gravity: about 13 °P
  • ABV: about 4.6%
  • Final gravity: about 4 °P
  • Hopping rate: 3.3 to 3.6 g/L
  • Boil time 2 hours, with hop schedule as described above
  • Hop variety: Saaz
  • Base malt: Vienna malt
  • Mashing schedule: triple decoction (more details here)

This information is pretty complete, and in fact quite detailed. The only things I would say are not 100% clear are the exact specs of historic Vienna malt such as colour, modification and barley variety (which means we need to trust commercially available modern Vienna malt), and the brewing water that was used. To give you a hint about what the ground water in Schwechat is like, you can find current water analysis data online. This is of course not a guarantee that the water profile is authentic. The water may have changed through 150 years of modern farming, and the brewery could have treated the local water, which would change everything. In any case, the important point about the water is that Viennese water is not necessarily right, as Schwechat’s water source is separate from Vienna’s, and Vienna’s water sources have changed in the last 150 years.

Nevertheless, quite a lot of information about Vienna lager has now been confirmed through historic sources, some of them even through multiple sources, which gives me greater confidence than ever before that Vienna lager brewed based on the specs above is as close to the historic original as possible.

#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.

Historic Vienna Lager: More Findings

During my preparations for #BeeryLongReads2018, I found more information regarding my historic Vienna lager. In particular, I found more information about one topic that has been quite difficult to find anything out about: hopping rates. I blogged about the hops used in Vienna lager previously.

In the book “Die Theorie und Praxis der Malzbereitung und Bierfabrikation“, published by Julius Thausing in 1888 (previous, less comprehensive editions, e.g. from 1877, are available), the author lists typical hopping rates for Vienna lager beers. The amount of hops varied depending on the original gravity:

  • 10.5%: 1.8 – 2.2 – 2.5 g/l
  • 11.5%: 2.5 – 2.8 – 3.0 g/l
  • 12.5%: 3.0 – 3.3 – 3.6 g/l
  • 13.5%: 3.3 – 3.6 – 3.8 g/l
  • 14.5%: 3.6 – 3.8 – 4.0 g/l
  • 15.5%: 4.0 – 5.0 – 6.0 g/l

Low-gravity beer was generally brewed with an OG of about 10% and sold after 6 to 8 weeks, while the regular Lagerbier was brewed with 13% OG and lagered for 4 to 8, sometimes even 10 months or more. This hopping rate is a bit lower than what I had found in other sources before, which prescribed a hopping rate of 4 g/l for Vienna lager.

Of course, with the absence of any information regarding alpha acid, the actual bitterness still remains a big miracle.

In the years 2006 to 2015, the alpha acid content of Saazer hops varied between 2.1% (2015) and 4.0% (2011); the average 3.15%, the median 2.9%. At a hopping rate of 3.6 g/l in a 13°P wort and 90 minute boil time, this can mean a bitterness between 19 IBU and 37 IBU! Most likely, the answer lies somewhere in-between, so for hops with 3.15% alpha acid, this would mean 29 IBU, which seems absolutely reasonable and is close enough to some of my previous estimations of 27 IBU. I take this as a confirmation that a hopping rate to achieve a bitterness of around 27 IBU to 30 IBU seems appropriate for Vienna lager, at least from a historical point of view.

Hops used in Vienna Lager

Two  years ago, I did some research to put together a recipe that was meant to closely match what a Vienna lager in the 19th century would have looked and tasted like.

About a year ago, I also discussed the state of Austrian hops and how the hop growing industry had changed over time. In that article, I mentioned that Kleinschwechater Brauerei used to own land in Michelob in Bohemia, close to Saaz, where the brewery grew barley and hops. Due to the geographical closeness, I made the point that most likely Saaz hops or a very closely related landrace would have been grown there.  But so far, I did not have any conclusive proof that Kleinschwechater (later Schwechater) Brauerei indeed brewed with Saaz hops.

That changed a bit when I visited the Schultze-Berndt library located at VLB and curated by the Gesellschaft für Geschichte des Brauwesens (society for the history of brewing technology) a few weeks. When doing some research for my English-language book on homebrewing historic beer styles, I stumbled upon a Festschrift regarding 100 years of brewing Vienna lager, aptly named “Schwechater Lager”. While not having that much content, it still had some bits and pieces that gave away some information, including the beautiful water colour illustrations.

One image in particular contained something very interesting: pictures of huge stacks of hop bales. 

These hop bales clearly show the marking “SAAZ”. Assuming that this picture accurately shows the hop storage facilities at Schwechater brewery, we now have a direct connection showing that Schwechater has been using Saaz hops. The text around it mentions that the brewery has been covering their demand using hops from Saaz, and praises Saaz as one of the best hop growing regions in the world. Unfortunately, no time frames are mentioned, so while all this information was certainly true for their brewing in the late 1930’s and early 1940’s, we cannot yet make the direct connection that Vienna lager in the 19th century must have used Saaz hops.

So let’s go a bit further, into the less colourful but more number-laden territory of raw statistics. In 1891 (that’s the earliest that I could find), Bohemia had 10317 hectares of hop growing land, producing an annual output of 77540 Zentner (1 Zentner = 50 kg in Germany, therefore 3877 tons). At that time, the total hop growing area of the Austro-Hungarian Monarchy was 14850.5 hectares (divided into the regions of Bohemia, Galicia, Styria, Upper Austria, Moravia and Carinthia), and the total annual output was 117534 Zentner (5876 tons). So for the whole of the monarchy, Bohemia produced almost 66 % of all its hops, on almost 70 % of its acreage allocated to hop growing.

This trend of Bohemia being the dominant hop grower within the monarchy continued in the years after as late as 1918, and Bohemia’s dominance even grew larger as other hop growing areas declined further: in 1913, Bohemia’s hop output was 73.8 % of the monarchy’s total output, with 75.8 % of the total hop acreage, while in 1914 it was a staggering 87.7 % (85.2 % of the total hop acreage). The stark increase in share in 1914 is due to a complete failure in Galicia for that year, most likely due to World War 1 and Austria-Hungary losing the Battle of Galicia.

So, just by looking at the pure numbers, we can deduce that there was a very high likelihood that most breweries bought their hops from Saaz. Again, this is not definite proof, but it points even more towards the direction that hops from Saaz were used by Schwechater brewery, and possibly most other breweries at that time, especially since Saaz hops were the highest priced ones in Germany and Austria at that time.

On a side note, the hop production of Bohemia at that time up as late as the late 1930’s was so strong that Germany’s annexation of the Sudetenland in 1938 pretty much doubled Nazi Germany’s acreage and overall amount of hops produced.

Vienna Lager: the Aftermath

The result.
The result.

As blogged previously, I had looked a bit into the historic roots of Vienna lager, a beer style that was quite successful in the 19th century in Europe, but has since then been forgotten in its country of origin, and had only been revived through the US craft beer movement.

In April, I finally managed to brew the beer, and it fermented and matured in the weeks afterwards. It’s been lagering for a while, but a few weeks ago, it was finally ready and also finished carbonating (I had kegged the beer and force-carbonated it). The end result is a good, quaffable lager at 5% ABV, though a bit rough around the edges.

What I do like about the beer is that it just puts the intense maltiness of Vienna malt in the foreground, accentuated by a bit of residual sweetness due to a very poorly attenuating yeast. What I don’t like so much about it is how the hops play together with this residual sweetness: even though I only used Saaz hops as the sole hop addition for bittering, the beer got a very spicy hop flavour. That would be great in a dryer beer, but with 4°P final gravity, it’s just a tad too sweet, and that just clashes a bit. Don’t get me wrong, it’s still a good beer, and I’ll happily drink it, but the next one I’d do differently. Definitely a better attenuating lager yeast, and maybe a different hop variety. I think I really need to research Austrian 19th century hops wrt. to what Anton Dreher used in his beers. As mentioned in one of my previous articles, it’s very unfortunate that Austrian hop land races were (presumably) lost either due to illnesses (which ultimately brought us Styrian Goldings) or a forced stop of any hop-growing activities by the Nazis (as it happened in Mühlviertel, Upper Austria).

Another lesson that I learned was that the WLP820 yeast strain, at least in its first fermentation, is extremely slow. I even employed a quick lagering schedule with which I had had success in previous beers, but it still took 3 weeks until fermentation completely stopped. At least it behaved pretty much as expected, and was only a tiny bit more attenuative than its historic predecessor. Starting at 13°P original gravity, it fermented down to 4°P, while brewing records show something closer to 4.5°P to have been the beer’s final gravity. That’s fine with me, really.

All in all, it was definitely an interesting exercise, with a tasty outcome, and I really learned what works and (more importantly!) what doesn’t with Vienna lagers.

Brewing a Vienna Lager

About a month ago, I posted about some things I found out about Vienna lagers, and how the historic original probably was like compared to modern versions of that style.

So yesterday, we finally got around to brewing it on my own. I compromised a bit in the whole process, though, just to make a few things a bit easier for me. In particular, I decided not to do a decoction mash.

I use a Weck preserving cooker as a mash tun, as it can contain plenty of liquid for the mash, and it’s electrically heatable, allowing to go through specific rest temperatures without having to resort to having to add hot water later. Just don’t trust the internal thermostat, and use a proper food thermometer instead.

I used 20 liters of water at 66 °C, and mashed in 5.3 kg of Vienna malt. The resulting mash was at 62 °C, and from there on I did a simple Hochkurz infusion mash:

  • 30 minutes at 62 °C
  • 20 minutes at 72 °C
  • 10 minutes at 78 °C

For modern malts and a high degree of diastatic base malts (like 100% in this case), that’s good enough to fully convert all starches.

After an iodine test showed that all starches were indeed converted, we continued with lautering. For that, we use a simple bucket from my preferred homebrewing online store, with a Mattmill false bottom.

For sparging, we always employ a colander with a food container lid set in the middle, to sprinkle hot water on the mash. BTW, my hot water is… my boiler. My flat contains a large boiler that actually delivers 80 °C hot water. Perfect for sparging.

 

The collected wort showed a pre-boil gravity of about 12 Brix, which later turned out to be probably not quite exact. I think I need to recalibrate it with distilled water. *sigh*

Anyway, we boiled it for 90 minutes, with 60 grams of Saaz hops for bittering, and no other hop addition.

After a whirlpool, I moved the wort to a fermentation bucket, and cooled it down to 20 °C with an immersion chiller, then moved it to my keezer to further cool it to 11 °C.

The hydrometer showed a bit more than 13 °P as original gravity, while the refractometer showed 14 Brix. A recalibration really seems necessary.

Finally, in the evening, I pitched a starter of WLP820 yeast. That should give a low attenuation comparable to the lager yeast that was used in the 19th century in Anton Dreher’s brewery. The beer is going to ferment in the next two weeks or so. I’ll use Brülosopher’s quick lagering method, as I’ve had some good experience with it in previous batches of lager brewing.

As soon as the beer is finished lagering and carbonating, I’ll post a report about the final result.

Tracing the origins of Vienna Lager

As an Austrian, I’m naturally interested in Austrian beer. One of the heritages of Austrian brewing is the Vienna lager beer style, a style that has actually long been forgotten in its country of origin, where the contemporary beer market has been dominated by beers that are almost, but not quite, entirely unlike German and Czech beers. Austrian Märzen is less alcoholic and a bit paler than Bavarian one, Austrian Helles is hoppier than the Bavarian counterpart, and Austrian Pilsner doesn’t have the same flavour profile like German or Czech Pilsners. The only German beer that to me that has a flavour profile similar to Austrian beers is Rothaus Pilsner.

Only recently, Vienna lager has been rediscovered in Austria: Brauhaus Gusswerk produces a very nice one, and with Ottakringer’s “Wiener Original”, there is even a mainstream supermarket beer of that old style (for the record, it’s one of my favourite local beers whenever I’m back in Austria).

Outside of Austria, and that’s what most literature will tell you, Vienna lager survived by getting picked up as a beer style by Austrian immigrant brewers in Mexico, and from there it was subsequently picked up by the thriving US-American craft beer scene. That’s a reason why the beer style’s definition is very much dominated by an American view on it, like the BJCP definition and the Brewers Assocation Beer Style Guidelines. And that’s where the problems begin.

Both style definitions contradict each other, with BJCP describing it with “Caramel aroma is inappropriate” and “No roasted or caramel flavor”, while the BA says “malty aroma, which should have a notable degree of toasted and/or slightly roasted malt character”.

I’m not entirely happy with either definition, just like I’m generally not very happy with what the BJCP writes about some other beer styles. So I wanted to find out what Vienna lager was actually like, originally, and whether an authentic recipe can be reconstructed.

To start of, I first needed to find out what the beer looked and tasted like. Emil Leyser, in his book “Die Malz- und Bierbereitung” from 1900, wrote (I only have excerpts, sorry) that Vienna beers have a golden yellow colour, a very rounded and full-bodied flavour with a low hop bitterness. He also explicitly states that the beer does not have anything caramelly or “assamar” (roasted bitterness).

In his book “Decoction!” (p.29), Ron Pattinson lists some beer analysis results from Viennese beers from 1870. One entry in that table is particularly interesting:

  • Beer: Lager
  • Brewery: Schwechat
  • Where sample obtained: direct from the brewery
  • OG beer: 1017.60
  • Balling wort: 13.25°
  • Balling beer: 4.51°
  • Apparent degree of attenuation: 65.94
  • ABV: 4.6
  • Lactic acid: 0.13
  • Colour: 6.3

It’s not entirely clear what unit of measure colour is. I assume SRM, for one particular reason: beers of that colour are usually described as golden, which would match Emil Leyser’s description.

What’s also quite interesting is how low the attenuation is. I assume “OG beer” refers to the gravity points of the finished beer, “final gravity” in modern terms. Balling is the predecessor of the Plato scale, and 4.51° for the final gravity are relatively close to 1017.6 gravity points. Full-bodied, indeed.

When going further in finding some bits and pieces, I also looked at what Ottakringer is writing about their modern version of Vienna lager: they say they use Vienna malt, Melanoidin malt, and Saaz hops. Their original gravity is lower than the 1870’s analysis (12 °P), and the amount of alcohol is higher, as well (5.3 % ABV), so their beer would be a lot drier than the historic beer. The ingredients are notable, though: Vienna malt as the obvious choice for the malt (it’s the malt that was expressly developed for Vienna lager, after all), Melanoidin malt, presumably to add more colour and to imitate the additional melanoidin production of a proper triple decoction, and Saaz hops as a classic noble hop variety. Saaz is considered a Czech hop variety nowadays, but don’t forget that in the 19th century, Bohemia was part of Cisleithania, the Austrian part of Austria-Hungary. At least from a historic point of view, it is an absolutely reasonable choice in hops.

Saaz was not the only hop growing region in Austria, though. In Mühlviertel, the part of Upper Austria north of the river Danube, there’s been (and still is) an active hop growing industry, as well. It’s hard to tell which varieties were grown in the 19th century, though, as production had ceased during World War 2, and after the war, hop gardens were repopulated with German, Slovenian and British hop varieties. Hops were grown in southern Styria as well, which is now part Austria, part Slovenia, but the hops there were replaced after problems with diseases in the early 20th century, and Styrian Goldings, a Fuggle with local terroir, and other hop varieties  bred from Styrian Goldings are grown there nowadays.

Now that we’ve generally established what malt and what hops would be appropriate, we still need to find the right yeast. Obviously bottom-fermenting, preferably Bavarian. Anton Dreher and Gabriel Sedlmayr had worked together in researching English brewing technology, and so it wouldn’t be unreasonable to think that Dreher would have gotten a bottom-fermenting yeast strain from Sedlmayr’s Spaten brewery.

Earlier, we already established the desired attenuation of only about 66 %. Wyeast has WY2308 “Munich Lager”, at 70-74 % attenuation, which is already pretty close to what we’re looking for. White Labs has WLP820 “Oktoberfest/Märzen Lager Yeast”, with an attenuation of 65 to 73 %. This looks much better already! They also offer WLP838 “South German Lager Yeast” (68-76 %), WLP860 “Munich Helles Yeast” (68-72 %) and WLP920 “Old Bavarian Lager Yeast” (66-73 %) that are a similar range of attenuation.

According to the Yeast Strain Comparison Chart, WY2308 is the same strain as WLP838, which apparently is the yeast strain “Wisenschaftliche Station #308” from Munich. According to the same chart, WLP820, the closest choice in terms of attenuation, is the “Weihenstephan 206” yeast strain, and the same as WY2206, which is specified to attenuate higher (73-77 %), though. Either the chart is a bit off here, or there has been some genetic drift in the propagation of one these strains. But for me, WLP820 sounds close enough.

So, based on this information, if I were to design a recipe for a Vienna lager, I would do it like that:

  • 100 % Vienna malt, enough to get a OG of 1053 (13 °P).
  • Ideally, a triple decoction mash.
  • A single bittering addition of Saaz hops, e.g. 3 g/l (3.5 % AA) for 90 minutes to gain 27 IBU*.
  • A cold fermentation with WLP820 yeast that should end up with a final gravity of about 1018 (4.5 °P).

(* I’d keep the bitterness at the higher end to counteract the very high final gravity)

Based on what I could find out, this would match the original beer style relatively closely. When you enter that into a recipe calculator, the typical colour you will get is about 6 to 7 SRM (about 12 to 14 EBC). This is much closer to how Vienna lager was described by Emil Leyser. It also is a lot paler than the style definitions of BJCP and Brewers Association, which specify a range of 10 to 16 SRM resp. 12 to 26 SRM.

(On a side note, the resulting recipe above is remarkably simple, in modern homebrewers terms, it’s a SMaSH (single malt and single hops) beer.)

Of course, this is not enough. A direct comparison with historic documents from the Klein-Schwechater Brauerei directly would be interesting, because this recipe is merely put together from bits and pieces, with plenty of (informed) guesswork to fill in missing gaps. If anybody has something like that, please contact me, as I would really like to see whether the historic original would confirm or deny what I put together here.

And of course, I haven’t brewed this beer yet. That’s an exercise for another time.