Tag Archives: water analysis

History, Water

An Attempt To Reconstruct Historic Vienna Lager’s Water Profile

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In the reconstruction of everything related to historic Vienna Lager, there is one piece missing that I’ve not been able to conclusively reconstruct so far: its water profile, and in particular, the water profile at Kleinschwechater Brauerei, where Anton Dreher first brewed Vienna Lager.

People who read my book on the subject are probably already aware of this, but for those who are not, a quick recap of the water situation there: the original Kleinschwechater brewery was located next to Kleinschwechat’s cemetery. The cemetery was on Löss soil (wind-blown silt sediment), while the brewery’s wells were dug into soil consisting of alluvial resp. diluvial gravel. By 1869, the brewery had four wells that had gone bad due to contamination from brewery and animal waste, so two further wells had been dug in the garden next to the brew house. Of these two wells, one’s water was used for brewing, for which we have a chemical analysis conducted in 1868 by Johann Karl Lermer. It looks like this:

  • Specific gravity of water: 1.00074
  • Total dissolved solids: 0.380 grams per litre (=380 mg/L)
  • Ash content: 0.296 grams per litre
  • Organic matter: 0.084 grams per litre

The dissolved solids were analysed and their constituents were listed in percent:

  • Sodium chloride: 2.53%
  • Chlorine: 3.86%
  • Sodium: 3.45%
  • Potassium: 3.94%
  • Calcium carbonate: 22.75%
  • Magnesium: 11.27%
  • Iron oxide: 0.30%
  • Sulfuric acid: 18.03%
  • Phosphoric acid: 0.22%
  • Carbon dioxide: 24.42%
  • Silicic acid: 2.52%
  • Organic matter: 1.49%

(please note that I think I previously misidentified the “Kalk” in the original German text as calcium oxide. It more likely means calcium carbonate, which I corrected in this list)

This is fairly detailed, but how does this get us to a modern water profile consisting of carbonate hardness, calcium, magnesium, sulfate, chloride and sodium? So here’s my attempt of trying to reconstruct that. Please be aware is that my last time I had chemistry lessons was 23 or 24 years ago. I also never thought myself to be a particularly good chemistry student.

I started off with the individual weight of each of the chemical compounds: 380 mg/L is equal to 380 ppm. Applying the percentage to the 380 ppm of should give us the respective ppm of each compound. Please note that I only listed the ones relevant for our water profile:

  • Sodium chloride (NaCl): 9.6 ppm
  • Chlorine: 14.7 ppm
  • Sodium: 13.1 ppm
  • Calcium carbonate (CaCO3): 86.4 ppm
  • Magnesium: 42.8 ppm
  • Sulfuric acid (H2SO4): 68.5 ppm
  • Carbon dioxide (CO2): 92.8 ppm

I then looked up the molecular formulas for each of the chemical compounds, as well as the molar masses of all the elements found in each of the compounds.

So now let’s use this data to reconstruct what we need in our water profile.

Carbonate Hardness

Carbonate hardness is basically the concentration of HCO3–(hydrogencarbonate) ions. While we do not have this one available directly, we can reconstruct the amount from the amount of CO2. The molar mass of CO2 is about 44.0088 g/mol, so adding the mass of one H and one C gets us about 61.01604 g/mol. When we apply this to the ppm of CO2 (92.8), we get an HCO3– concentration of 128.7 ppm, or 5.9 °dH (German degrees of hardness).

Calcium

For the calcium content, we need to go the other way, and look at the calcium content of the calcium carbonate. CaCO3‘s molar mass is about 100.0088 g/mol, while Ca’s molar mass is just 40.08 g/mol, so the 86.4 ppm of calcium carbonate should translate to about 34.6 ppm of calcium, or 4.8 °dH.

Magnesium

That one is easy, because it’s listed directly, with 11.27%, which translates to 42.8 ppm.

Sulfate

The sulfate ion is SO42-, so we should be able to reconstruct it from the sulfuric acid (H2SO4) content, following the same approach as with the calcium. H2SO4‘s molar mass is about 98.08 g/mol, while SO42- is about 96.06 g/mol, so the reconstructed sulfate content should be 67.1 ppm.

Chloride

Chlorides are either chlorine ions or chlorine atoms bound to molecules by a single bond. In Lermer’s analysis, we have two chemical compounds that involve chlorine atoms: chlorine, and sodium chloride. From the chlorine, we can simply assume the same ppm (14.7 ppm), while for the sodium chloride, we need to calculate its portion (5.8 ppm). When we add both, the total chloride content should be 20.5 ppm.

Sodium

Similar to the chlorides, we have two chemical compounds that involve sodium atoms: straight up sodium, as sodium chloride. Following the same approach, we can take the ppm of sodium (13.1 pm) and add the sodium portion from the sodium chloride (3.8 ppm). This means we end up at 16.9 ppm sodium content.

The final water profile

With all this, we end up with this water profile:

  • Carbonate hardness: 128.7 ppm, or 5.9 °dH
  • Calcium: 34.6 ppm, or 4.8 °dH
  • Magnesium: 42.8 ppm, or 9.9 °dH
  • Sulfate: 67.1 ppm
  • Chloride: 20.5 ppm
  • Sodium: 16.9 ppm

My question to all you people out there with a better knowledge of basic chemistry than me: does this make sense? Provided the German terms for the individual chemical compounds that I translated to English mean exactly what I think they mean, does it make sense to derive the amounts of ions in the water from the amount of molecular compounds determined in that chemical analysis?

Please let me know in the comments whether this attempt of reconstructing the historic water profile of Vienna Lager at Kleinschwechater brewery (at least as analysed in 1868) makes sense or not.

(thanks to Ben for proofreading the article before I published it)

Beer Styles

The Water Profile for Vienna Lager

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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.