Category Archives: Brewing

My Summer Beer 2022

Like last year, I decided for 2022 to brew a light and refreshing beer for the the summer. I was really really happy with my 2021 beer, and so for this year, I again brewed an 8° Czech-style beer, this time even more traditional than last year.

And that was my exact approach: be as simple as possible, but stick to the ingredients that would constitute a Czech beer according to PGI (if I brewed commercially in the Czech Republic and wanted to sell my beer with a Czech Beer PGI label): the sugar from the wort needs to be at least 80% from Czech barley varieties, at least 30% of the alpha acid needs to come from Czech hops varieties, decoction mashing needs to be used, and the beer needs to be bottom-fermented. So I went all in:

The brewing and fermentation process itself was rather uneventful: I hit 8.4°P OG, chilled the wort to 10°C, pitched a yeast pack, fermentation took off in less than 36 hours, and after about 3 weeks, it was finished, with a FG of 2°P. I then ramped down the temperature to 2°C, let it sit at that low temperature for just 2 weeks, and then bottled it, bottle-conditioning it with 1 liter of wort that I kept back.

I’m absolutely impatient when it comes to waiting for beer to be finished maturing and bottle-conditioning, so I had to crack one bottle open after just 1 week. I pre-chilled it for a few hours, and then poured it into a Pilsner Urquell glass I had at home. While carbonation wasn’t 100% there yet, it was definitely enough to drink it. The foam was fluffy but with rather big and open bubbles (I hopes this improves when carbonation is higher), the beer still looked slightly hazy with a very pale colour). It smelled absolutely amazing, and just after the first sip I could definitely say that this was exactly like a Czech beer (it’s not a Czech beer because I brewed it here in Berlin, hence why I call it Czech-style). It has that exact bitterness and the kind of hop flavour and aroma that I would expect from any Czech beer, it has a unique edge to its malt character that I would attribute to the intense decoction mash (hard to describe, but once you’ve had plenty of Czech beers, you just notice it, from your easy-drinking 10° beers to modern Czech-brewed IPAs e.g. from Matuška), and it’s got a very good body for such a low-strength beer.

The Urkel Lager strain, despite (allegedly) having a Pilsner Urquell provenance, does not seem to produce diacetyl at any detectable levels. What it does though is produce lots and lots of sulphur. This was particularly noticeable during fermentation and at the beginning of the very short lagering period, but at packaging, all of that was gone.

In the end, choosing the right ingredients and processes for the kind of beer you want to brew matters, and I’ve only ever gotten all the details of a Czech-style beer right when I applied all the techniques that I knew, with all the right ingredients.

What follows is a quick recipe. In terms of ingredients, it’s incredibly simple and one of those beers that can be formulated as a SMaSH beer – single malt and single hops. In this case:

  • 3.1 kg floor-malted Bohemian Pilsner malt from Weyermann
  • 24 g 2021 harvest Saaz hops (4.2% ABV) @ 60 min
  • 24 g 2021 harvest Saaz hops (4.2% ABV) @ 30 min
  • 24 g 2021 harvest Saaz hops (4.2% ABV) @ 5 min
  • 1 pack Imperial Yeast L28 Urkel Lager yeast

Use enhanced double decoction mashing scheme. Lauter, sparge, chill to 10°C, pitch yeast. Ferment fully, lager at low temperature for 1 week (I went down to 2°C), bottle or keg and carbonate. This should get you about 20 liters of a beer with 8.4°P OG, 2°P FG, 3.4% ABV, about 25 IBU in bitterness, and a very pale colour.

Experience in Brewing a Belgian-Style Tripel

I’m not really an expert on Belgian beer styles. I do like my gueuzes and lambics, and there are some Belgian beers that enjoy occasionally (my wife and I keep a collection of various vintages of Orval), but my personal interest is not exactly focused on Belgian beer, and therefore I don’t seek them out regularly or brew them at home.

My Dutch neighbour Rick though, he’s very much into Belgian beer styles. When he learned that I knew how to brew beer at home, it was clear that we had to brew something together. I asked him what his favourite beer style was (it’s Tripel, with his favourite beer being Tripel Karmeliet), and so we decided to brew a Tripel. Prior to that, I had only brewed one Tripel that was loosely inspired by Brooklyn Brewery’s Local 1. So off I went to do a bit of research.

My first decision was to make the base mostly Pilsner malt, and use some sort of sugar so as to make the beer “thinner”. With a high original gravity, you’d expect the final gravity to be fairly high and the beer to be full-bodied, so adding sugar to amp up the original gravity but keep the final gravity at a fairly low level is the way to go.

With the hope of adding a bit more complexity to the malt profile of the beer, I decided to also add 500g of flaked spelt. Not only is it a fairly cheap and easy to get ingredient, it could potentially also impart its own flavour to the beer, and (as a relative of wheat) also help with head retention.

When it came to the choice of sugar, I first looked at what my options are with pale candi sugar. Turns out, candi sugar syrup from home-brew stores is really expensive, and so I decided to look into other types of sugar. I found a slide deck “The Sugars of Tripel” by Ted Hausotter which discusses several option in great detail and also involved some experimentation. If you plan to brew a Tripel yourself and are thinking your sugar options as well, don’t miss this presentation. Looking at the slides of tasting results and rankings of the type of sugar used, I opted to go for cane sugar, as it seemed an okay option that also didn’t deteriorate flavour-wise over time. There was some warning that sucrose could add a slight cidery note to the finished beer, but I was willing to risk that.

As for the yeast, I took a closer look at what my options were with dry yeast. Fermentis has two options that could roughly fit the phenolic and estery profile of Tripel, namely SafAle BE-256 and SafAle T-58. Lallemand also has two options, one is their LalBrew Abbaye, the other one a more recent offering that might seem a bit unusual at first: LalBrew Farmhouse, which they describe as a hybrid-style saison yeast. Unlike most other saison strains, this one is non-diastatic, meaning the yeast is missing a gene that would otherwise help it enzymes to break unfermentable sugars down to help ferment a beer to absolute dryness.

When I came across that product, it actually got me thinking: normally, saison yeasts are a bit more phenolic in their flavour profile, but if that yeast is indeed non-diastatic, I could end up with a beer less dry and still with enough body to make it a convincing Tripel. What’s the worst that could happen? If the flavour profile does turn more towards a typical saison, I’d have something akin to Dupont Bons Voeux. So let’s be a bit experimental.

When it came to hopping, I wanted to have enough bitterness and hop aroma so as not to make this beer too sweet. It’s what I had noticed with some Tripels, and Joe Stange had also mentioned to me in the past that Tripels can work surprisingly well even with higher levels of bitterness. I think his prime example was Westmalle Tripel. When aging strong beers, my experience is that you could lose quite a bit of noticeable bitterness, so it’s better to aim too high than too low. In the end, I decided for go for 1g/L of Herkules (16.7% alpha acid) as bittering addition, 1g/L of 2021 harvest Saaz hops (4.2% alpha acid) as flavour addition (30 minutes before end of boil), and 2.5g/L of the same Saaz hops as late aroma addition (5 minutes). In terms of calculated IBU, this should end up at about 38 IBU.

The brew day itself was fairly relaxed: Rick and I mashed in 5.2 kg of Bohemian Pilsner malt and 500g of flaked spelt, did an initial protein rest for about 15 minutes at 54°C, then ramped up to 62°C for saccharification for about 40 minutes, and then 72°C for another 30 minutes, finished off with an increase to 78°C. Lautering and sparging went fine, and we mixed in and dissolved 1.2 kg of cane sugar (an organic own brand from a local health and beauty retailer that is ever so slightly darker than regular table sugar). After 60 minutes of boiling and adding all our hop additions according to schedule, we chilled the wort to 20°C, measured OG (19°P) and pitched two sachets of the Lallemand Farmhouse yeast.

I had originally planned the recipe for an OG of 18.5°P, but for whatever reason, we had slightly higher extraction and got 19°P. Surely not a bad thing.

After about 2 weeks, the beer was fully fermented. We then bottled it, using the same cane sugar for priming, and then let it sit for a few weeks for bottle-conditioning. The final beer came out at 2.7°P FG, which means that the final beer should have about 9.2% ABV.

We finally sampled the first bottle together this Friday. The resulting beer was actually less bitter than expected, and the hop aroma was more subtle than what I had expected, but nevertheless present in sufficient amounts. The beer itself looked slightly hazy, with a pale orange tone that made it look very inviting. The foam was very white, long-lasting and pretty dense, while the carbonation was exactly the right amount to make it pleasantly fizzy but not overly so (we went for about 2.5 volumes / 5g/L carbon dioxide). As for the flavour of the beer itself, I think the yeast expressed a very balanced amount of fruity ester and spicy phenols without either of them being too much in your face or overpowering anything. The body is just right, not too dry and not too full, which makes the beer dangerously easy to drink. The alcohol does not show at all, it is very smooth and slightly warming, and no cidery note from using cane sugar was noticeable. Rick (as a home-brewing newbie and Belgian beer aficionado) was very happy, and so was I, as I hadn’t brewed this style much beforehand, and therefore was really just guessing my way into a recipe based on some reading about the style that I had done.

(it glows more when held against the light)

The choice of yeast, although a bit risky because it was supposedly not an ideal match for the style, was a good call, and I can absolutely recommend Lallemand Farmhouse dry yeast for Belgian Tripels and similar styles. Keeping the grist simple with just Pilsner malt and spelt flakes also turned out to be a good choice, as was the use of cane sugar.

To summarize the recipe:

  • 5.2 kg Pilsner malt
  • 0.5 kg flaked spelt
  • 1.2 kg cane sugar
  • 20 g Herkules hops (16.7% alpha acid) @ 60 minutes
  • 20 g Saaz hops (4.2% alpha acid) @ 30 minutes
  • 50 g Saaz hops (4.2% alpha acid) @ 5 minutes
  • 2 sachets Lallemand Farmhouse hybrid saison yeast

Mash in and do multi-step infusion mash as described above (54°C, 62°C 40 min, 72°C 30 min, 78°C mash-out), lauter, sparge, add cane sugar to wort, boil 60 minutes with hop additions as describe above, chill to 20°C, pitch yeast, package with carbonation level of 2.5 volumes / 5g/L.

My Summer Beer 2021

Due to a rather bad episode of COVID, I hadn’t brewed a beer since October 2020, a Helles, which, when I bottled it in April this year, didn’t properly bottle-condition, and instead became an oxidized mess.

So this beer was a fresh start, my first home-brewed beer in a long time, and just something I wanted to have for myself. When I developed that recipe, I got inspired by two things:

First, the Czech Republic’s culture for lower-alcohol beers, with original gravities of 10°P or lower, and moderate amounts of alcohol of 4% ABV and lower.

Second, a particular Leichtbier that I had at Mahrs Bräu in Bamberg, which they call Sommerpils: it’s a very bitter beer at only 2.8% ABV and 7.2°P OG, and the first time I realized that highly hopped beers with low ABV can work really well.

After some thinking, I came up with an idea: I wanted to create a Czech-inspired 8° beer, with a good amount of bitterness coming from a late hop addition at flameout. One particular hop variety that I really liked in the past was Brewers Gold. I had used it in a Golden Ale previously, and it just gave off lovely citrusy notes with a fruitiness that some describe as blackcurrant.

But why would I call it Czech-inspired? First of all, the OG: 8°P is something that you would in the Czech Republic more often that in e.g. Germany. German Leichtbiere are typically even lower than that.

Second, the grist: I decided to stick to just Bohemian Pilsner malt and a small ~3% addition of a dark caramel malt, in my case CaraBohemian.

Third, the mashing regime: I’m a huge fan of double decoction. Even though it takes a long time, it has given me very good results in previous beers. In particular, I’m using an enhanced double decoction scheme that basically skips protein rest or keeps it to a very short amount time. Decoction mashing is also extremely common in Czech brewing.

Fourth, the bittering hops: I used Saaz hops simply because I had them available, they’re reliable and suitable for what I wanted to achieve. As aroma hops, as mentioned above, I got Hallertau-grown Brewers Gold.

Let’s quickly compare this to the PGI regulation for the term “Czech Beer”: at least 80% of the sugar in the wort needs to be from malt from Czech barley varieties (which I assume Weyermann’s Bohemian Pilsner malt should fulfill), at least 30% of alpha acids from hops must come from Czech hop varieties (I’m using Saaz for bittering), local water must be used (I do that), bottom-fermenting yeast must be used, and decoction mashing must be used. I’d say I’m pretty close, except I don’t brew in the Czech Republic, nor do I attempt to get any PGI Czech Beer certification for my home-brewed beer. Nevertheless, the regulation is still a good indicator of what’s considered to be traditional or necessary for Czech beer, and therefore also serves as a good template for Czech-style or Czech-inspired beers.

Grist, hop additions, yeast and basic numbers.

The brew day itself was relatively uneventful, except for a slightly higher than expected OG of 9.4°P. The 8° beer became a 9° beer. I can cope with that.

I chilled the wort, pitched plenty of Lallemand Diamond Lager yeast, and just let it ferment. When the beer was fully attenuated, I decided not to bother with lengthy lagering, but instead just slowly lowered the temperature down to -1°C, kept it there for a few days, and then bottled the beer.

My Czech-inspired beer is now bottle-conditioned and ready to be consumed. When I first poured it, I was surprised about how hazy it was. Even after several more days in the fridge, it still remains hazy. I blame hop haze from the flame-out addition, but to be honest, I don’t actually care. Because the beer itself tastes great.

It’s got a full body, at a FG of 2.2°P, and with 3.9%ABV, it’s a very drinkable beer with a robust bitterness that lingers on. The Brewers Gold hops provide a nice citrusy flavour, but its additional fruitiness in the aroma combined with a slightly lower than expected carbonation (my fault) gives the beer an English Bitter vibe. Brewers Gold was originally an English hop variety, and it still shows in this bottom-fermented beer.

All in all, I’m really happy with the result. It’s a nice, refreshing beer perfect for a hot summer. I still have ~17 litres in my fridge that likely won’t last till the end of summer.

And finally, a photo of what the beer actually looks like. An alternative title for this blog post that I had in mind earlier was “my crispy boi is also a hazy boi”.

A Conversion Chart Between Beer Colour Scales

In a recent Twitter discussion about beer colour and colour scales, Ron Pattinson said how handy it would be to have a conversion chart between colour scales, ideally for Lovibond, SRM, EBC, Stammer (famously used by Professor Schwackhöfer in his 1876 analyses of beers sold in Vienna) and “Einheiten nach Brand”. In particular, the discussion revolved around the latter, as it’s one of the scales used in TGL 7764, East Germany’s industry standard for beer.

TGL 7764 is a particularly interesting industry standard, as it’s a rare example of beer styles getting standardized down to original gravity, bitterness, beer colour and even beer label colour and (in the case of Porter) microorganisms (Brettanomyces). And unlike style guidelines nowadays, like BJCP or the Brewers Association’s ones, this was actually prescriptive, i.e. it was compulsory for breweries in the GDR to follow these beer styles. I’m not aware of any other country doing that, but then, I haven’t really looked into it systematically.

Unfortunately, there does not seem to be a linear relationship between the Brand scale and EBC, so a simple conversion based on a few data points that we have from the 1980 and 1986 versions of TGL 7764 (which uses NFE, Brand, K450 and EBC) is not possible. Nevertheless, I’ve looked at the conversion between Stammer and the other common scales in the past and even put a simple table in my latest book, so I took this as a chance to at least present the data that I already have.

I will try and find out more about the Brand scale and if I do, I will update this table accordingly.

Conversion Formulas

Stammer to Lovibond: °L = Stammer / 1.38

Lovibond to SRM: SRM = 1.3546 × °L – 0.76

SRM to EBC: EBC = SRM * 1.97

Conversion Table

EBCSRMLovibondStammer
1.00.50.91.3
2.01.01.31.8
3.01.51.72.3
4.02.02.12.8
5.02.52.43.4
6.03.02.83.9
7.03.63.24.4
8.04.13.64.9
9.04.63.95.4
10.05.14.35.9
12.06.15.17.0
14.07.15.88.0
16.08.16.69.0
18.09.17.310.1
20.010.28.111.1
25.012.79.913.7
30.015.211.816.3
35.017.813.718.9
40.020.315.621.5
45.022.817.424.0
50.025.419.326.6
60.030.523.031.8
70.035.526.837.0
80.040.630.542.1
90.045.734.347.3
100.050.838.052.5

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.

My Beer At Slosh 2019

On May 4, Berlin’s homebrewing competition SLOSH happened at BRLO brewery. I took part with a beer myself. I didn’t win anything, but it was nevertheless a good event to serve samples of your own beer, drink beer, and talk homebrew.

In total, 37 or so homebrewers took part, serving 40-something different beers. The competition mode is different what you may know from other competititons: brewers were divided up into 8 different tables of 4 to 5 brewers each, labelled A to H. Every brewer and visitor could vote on the beers of another table, selecting their three favourites, giving them 3, 2, and 1 points respectively. Obviously, brewers were assigned different tables to vote on than their own.

At the end of round one, the points were added up, and the most popular beer of each table was selected for round two. In this second round, professional judges tasted the beers and selected an overall winner.

Of course, this mode makes it relatively hard to choose the “right” beer style to win over other homebrewers as well as visitors, as crowd pleasers would more likely be voted favourite than just technically well-executed beers. My table was a relatively strong one: besides my own beer, a Golden Ale inspired by our last year’s visit of New Zealand, there was a citrusy Pilsner (quite classic, but with a late addition of Pacifica hops), a Saison hopped with (IIRC) Galaxy hops, and a NEIPA. From what I’ve heard, the votes were relatively close, and in the end, the NEIPA won.

As for my NZ Golden Ale, it suffered from my “competition curse”. So far, not a single beer that I submitted to a competition worked out as intended: 4 years ago, a Czech pale lager (essentially a PU clone) got oxidized rather badly when bottling and therefore scored rather poorly. 3 years ago, two beers that I submitted (a Saison and an ESB) got mixed up, and the ESB also caught an infection when bottling. The Franconian-style Kellerbier (inspired by Mahrs aU) didn’t work out because the dry lager yeast I used stalled twice, once at lager temperature, and once at room temperature, and so the beer never finished and was dumped. And this year’s beer, that’s a story on its own…

When we brewed our NZ Golden Ale, everything went fine until we went to boil the wort. That’s when we found out that the immersion heater that we use to boil the wort had broken. I normally boil in an electric cooker, but the cooker’s own heating element is a bit too weak to bring 25+ liters of wort to a full boil. I nevertheless tried that, but even after 3 hours or so, I still couldn’t bring it higher than 90°C. So I had to improvise, and split up the wort between two electric cookers (the second one normally functions as a kettle to boil decoctions, and later on as hot liquor tank).

With pouring the wort back and forth, I think I unnecessarily oxidized the wort, making it darker that what I had planned for. Also, the boil-off rate was quite different, so instead of ending up with a 11°P wort, I instead got a 13.5°P wort.

I was also worried about possible underpitching, so I pitched two sachets of Nottingham Ale dry yeast. Unexpectedly, this caused a very rapid and intense fermentation which finished only 72 hours after pitching. The resulting beer had a slight taste of fusel alcohol, confirming my suspicion that the beer may have heated up too much during fermentation at room temperature. In total, I wasn’t super happy about the result, but nevertheless served it at yesterday’s competition.

The overall feedback was surprisingly positive, and fortunately for me, serving the beer cold masked the unpleasant fusel alcohol notes.

Here’s the recipe:

  • 4.5kg Pale Ale malt (it was kindly provided for free by competition sponsor Weyermann)
  • 20g East Kent Goldings (5% alpha acid) – 60 minutes boil
  • 40g Nelson Sauvin (10.8% alpha acid) – whirlpool
  • 20g Waimea (15.5% alpha acid) – whirlpool
  • 2 sachets of Nottinghame Ale dry yeast, rehydrated

Unlike most of my other brews, the mash was simple: just 60 minutes of mash at 67°C, then lautering, and then boiling for what was planned to be 60 minutes (see above). I used East Kent Goldings hops for bittering. After the end of the boil, I waited until the wort was down to 94°C to reduce the amount of additional bittering contributed by the whirlpool hopping, and then added the whirlpool hops for 20 minutes. I then transferred the wort to the fermenter, chilled it down to 20°C, pitched the yeast, and let it do its thing.

The outcome were 18 liters of Golden Ale with an OG of 13.5°P, and 5.7% ABV (stronger than your typical Golden Ale). The colour of the beer goes very much towards orange rather than gold, and probably due to the large amount of whirlpool hops, it also looks rather hazy and never dropped bright.

Why a Triple Decoction Mash Can Never Fail

I’m currently working on a new project, so as part of that, I’ve been reading quite a few historic descriptions of decoction mashing, in particular triple decoction which historic literature generally describes as the standard mash schedule in Bavaria, Bohemia and Austria around the 1870’s-1880’s.

When I played a bit with calculating the right mash volumes and the mash temperatures, I stumbled upon an interesting property of standard triple decoction: you can’t get it wrong. You actually have to actively try and sabotage it for it to fail.

This is a really cool thing because triple decoction sounds so ancient and complicated and easy to do wrong, and I think that scares a lot of people who then shy away from trying it out, but if you follow a few simple principles, you can’t go wrong at all.

These principles are:

  • always pull 1/3 of your total mash volume as decoction
  • pull the first and second decoction thick (i.e. mostly malt with little liquid), and the third decoction thin (i.e. mostly liquid)
  • bring each decoction to a boil, boil for a bit, then mix back into main mash
  • make sure you measure your volumes exactly, work quickly when mixing back, but also mix thoroughly
  • when doughing in, give the enzymes some time to get dissolved before starting to pull your first decoction

From a historic point of view, triple decoction was a reliable method to guide your mash through a number of particular ranges of rest temperatures to facilitate the activity of specific enzymes to convert long proteins into shorter protein chains and to convert starch into simple sugar molecules and shorter dextrin chains to both achieve a fermentable wort and a good mouthfeel, without requiring a thermometer.

And when you apply some maths, and draw a pretty graph, it really shows that all you need is the ability to vaguely judge your initial mash temperature to be between somewhere slightly above room temperature and slightly below tepid, and everything falls right into place, provided you follow the principles above.

The general equation to calculate your decoction volume is:

decoction volume = total mash volume * (target temperature – start temperature ) / ( boil temperature – start temperature)

If we assume the total mash volume to be 1, and our decoction volume to be 1/3, we can rewrite this to

target temperature = start temperature + 1/3 * (boil temperature – start temperature )

Based on this, we can easily calculate whole temperature series if all we do is repeatedly pull decoctions that are 1/3 of the whole mash volume, bring them to a boil, and mix them back.

I’ve done this in a spreadsheet, and put this into a nice temperature/time chart to indicate the time schedule your mash steps would follow. In total, I’ve done this with four different initial temperatures: 20, 25, 30 and 35 °C. This is a rather wide temperature range, but it’s also one where most people could easily and correctly judge whether a liquid is within that temperature range just by feeling with their finger or elbow. To keep the chart readable, I’ve only added the main mash temperature, and left out the temperature curves of the decoctions. To account for cooling during mixing back, especially so on a homebrew scale, I assumed a boiling temperature of 95 °C instead of 100 °C.

Triple Decoction Mash Temperatures

In addition, I’ve marked the temperature ranges in which you reasonably want to keep your mash to do a protein rest, as well as to give the alpha and beta amylases good conditions to do their work.

When you now look at the chart, it is very noticeable that at all stages (protein rest, maltose rest, saccharification rest/mash-out), all our target temperatures fall within the desired temperature ranges. The further we go, the more all the temperature curves converge towards a narrower and narrower temperature range, even though we started with a very wide one. This makes it very hard to screw up, even if you e.g. slightly miss your target temperature after your first decoction: you will still be well within the desired temperature range.

In addition to that, when you bring up your decoctions, in particular the first one, to a boil, they go through these temperature ranges as well. Some modern mash schedules recommend doing at least a saccharification rest to optimally use the enzymes that will later get destroyed, so you can have an infusion step mash within your decoction. Even if you don’t do it, unless you heat up very quickly, your decoction will at least partially convert when you heat it up.

And this is why your triple decoction mash can never fail: when bringing your decoctions to a boil, they will partially, if not mostly, convert, and then release more starch during the boil, which will then be fully converted in the main mash. There are two decoctions where the enzymes get into the right temperature range to convert starch into sugar, and there are two rest steps where the enzymes have even more time to convert more starch into sugar. Your whole mash goes through the right temperature so many times, it will eventually be fully converted. And to get into these right temperature ranges, all you need to do is follow a few simple principles. And if you want, you could even do this totally without a thermometer.

For most modern malts, triple decoction is possibly a bit to harsh, in particular when it comes to the extended protein rest which could potentially be very damaging to foam stability. For this, you can also employ an enhanced double decoction, in which you start at the same temperature as a triple decoction, but pull double the volume for the first decoction, and do a step mash of your first decoction before boiling it. That way you keep the intense treatment of your malt, but can keep the time within the protein rest range to an absolute minimum.

The Theory of Brewing Reinheitsgebot-Compliant Brut IPA

Watch out, NEIPA, there’s a new fad in town: Brut IPA. If you haven’t heard of it yet, Brut IPA is a new IPA-inspired beer style with a dry body, low bitterness, high hop flavour and aroma, and high carbonation. One core element of achieving such a dry and hoppy but not bitter beer is to only add hops during flame-out or whirlpool, to dry-hop in the fermenter, and most importantly, to use enzymes during fermentation to convert any remaining complex sugars into simple sugars that the yeast can turn into alcohol and carbon dioxide. This unique combination of dryness, hop aroma, and high carbonation apparently gives the beer a very unique mouthfeel and sensory experience otherwise only found in highly attenuated and carbonated styles like Saison.

Brut IPAs haven’t really arrived in Germany yet (I hear there’s one or two small breweries releasing some), so I haven’t had the chance to try any examples yet. But from everything I’ve read so far, professional brewers who have done the style emphasize the use of enzymes to produce a highly attenuated beer. The problem with brewing such a beer in Germany is that enzymes would be an additional ingredient that’s currently normally not allowed to be used in brewing. So how would a brewer get around it?

Maybe let’s just first talk what the enzymes really are about. Basically, malt contains enzymes, called amylase (alpha amylase and beta amylase, to be more precise) , that break long starch chains into shorter bits. Beta amylase chops off simple sugar on the end of such a starch chain, while alpha amylase chops it up at any point of the chain, producing shorter and shorter chains, eventually ending up with unfermentable dextrins, or given enough time, simple, fermentable sugars. It’s the foundation of mashing, really. These amylase enzymes work at an optimal temperature range, depending on the specific type, between roughly 60 and 75 °C.

The thing with enzymes in Brut IPAs is that they are often added to the wort at the beginning of or during fermentation. A common product for that is glucoamylase, also known as amyloglucosidase or gamma amylase. While its optimum temperature is about 65 °C, it will still work at normal fermentation temperature and help with chopping up the last few remaining dextrins into fermentable sugars.

So, if German pro-brewers aren’t allowed to use enzymes to add to the fermenting beer, how else would they be able to achieve such a highly attenuated beer? Fortunately, there’s a precedent in recent German beer history. In Germany, you used to be able to buy Diätbier (“diet bier”) until the use of the term was prohibited in 2012. Diätbier is essentially a fully attenuated beer with no carbohydrates in it left, and it used to be advertised to be suitable for diabetics. This of course ignored the fact that alcohol changes the way sugar is absorbed by the body, and was one of the reason why Diätbier is not a thing anymore. But how Diätbier was free from carbohydrates is what made it similar to Brut IPA. So if we wanted to brew a Brut IPA that complies with German beer legislation, all we needed to do was to brew it just like German brewers used to brew Diätbier. There are a few approaches, which I’ll describe here:

The crudest and simplest approach is to just add a certain amount of barley malt flour to the chilled wort or freshly fermenting beer. The amylase in the beer will get active and not only convert the starch from the barley malt flour, but also any remaining dextrins, and given enough time, produce a beer with no residual extract. The risk there is that not all the starch will actually get converted, and starches in the final beer can have a negative impact on the overall shelf stability.

A better way and slightly more sophisticated way is to just take some of the mash when it’s at 60 °C to make sure none of the enzymes have been damaged, lauter it, put the wort aside, and continue brewing as normal. When the main wort is chilled and yeast has been pitched, the wort put aside earlier can be added to it, and the enzymes now have time to convert the remaining complex sugars and dextrins.

But wort can easily spoil, so you can go even further and produce a sotrable malt extract that can be used as enzyme source in brewing by mashing in malt at up to 65 °C, lautering, chilling, and then fermenting it. Without a boil, none of the enzymes should get denatured. The resulting unboiled beer can then be filtered to free it from proteins and yeast and kept for a longer period of time. Since it’s beer, it can be blended with other beer and still totally be within the purity law. This method was even patented in the 1980’s to a German company.

Practically, it’s probably the easiest for homebrewers to use the unboiled wort method. I would consider using barley malt flour to be unsafe, not just because of the risk of introducing starches into beer, but also for a slight contamination risk. Fermenting and filtering an enzyme-rich wort is probably also not great for homebrewers as you need to plan ahead and actually have the equipment and facilities to filter and package the beer in an contaminant-free environment. So the easiest is just to take a bit of wort during the mash, set it aside, and then add it to the fermenter a few hours later.

There’s also another way of achieving such high attenuation: super-attenuating yeast. There exist variants of brewers yeast, such as Saccharomyces cerevisiae var. diastaticus, that produce their own glucoamylase to help with converting starches and dextrines. Saison yeast is a well-known example for this type of yeast. Unfortunately, most diastaticus yeasts are also known for producing phenolic off-flavours (they are “phenolic off-flavour positive”, or POF+). In Saisons, these phenols are appropriate, while in other beer styles, such as IPAs, where the hop flavour and aroma should shine, probably not so much. So far, there are only two known diastaticus strains that are POF- (i.e. don’t produce phenolic off-flavours), which are WLP026 (an English ale yeast) and WLP644 (a yeast that had previously been misidentified as Brettanomyces since it is known for producing some funky, Brett-like aromas and flavours). This method is probably most suitable if you want to produce a “Belgian-style” or funky Brut IPA.

So, to summarize, if you want to brew a Brut IPA, and for whatever reason, have to stick to German beer legislation, and can’t or don’t want to add enzymes to your beer, or you can’t buy any glucoamylase in your homebrew shop, here’s a method that has been used in the past to produce very dry, highly attenuated beers. Just be aware that I haven’t actually tried this method in practice. Not only is it slightly too warm to brew beer unless you have good temperature control, I also didn’t really have time recently to brew much. This is just based on theory I read about in German brewing books.

If you want to learn more about Brut IPA, there’s been quite a lot of good stuff out there recently.  The Craft Beer & Brewing Magazine‘s August-September 2018 issue has a focus on IPAs, with a great article specifically about Brut IPAs. The New To Brew blog also posted an article about how to design and brew Brut IPAs back in June. So if you want to brew the latest hyped sub-style of IPA, there’s plenty of material how to do it right.

#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.

A little story about two historic mashing processes that didn’t quite work out

Let me tell you a little story about two historic mash processes that I discovered by pure chance, and how neither of them quite worked out. But there’s still stuff we can learn from them.

During some beer-related research, I stumbled upon a brewing book I hadn’t seen before, “Handbuch für den Amerikanischen Brauer und Mälzer” (“manual for the American brewer and maltster”), written by Ernst Hantke and published in 1897. This was odd, I thought, because it specifically referred to American brewing, and yet was published in German. Hantke was born in Silesia, and grew up in Germany. He studied chemistry, and landed a position as assistant of Dr. Delbrück at the “Versuchs- und Lehranstalt für Brauerei”, better known as VLB Berlin. In 1893, he emigrated to the United States, where he first worked as instructor at the American Brewing Company, and later accepted a job at the Valentin Blatz Brewing Company in Milwaukee, Wisconsin.

Milwaukee at that time was the epicenter of German-American brewing, four of the largest American breweries at that time were based there, Miller, Pabst, Schlitz, and Blatz, all of them founded by German immigrants to the US at some point during the 19th century. Among American brewers, Hantke’s book was well-received, his epitaph in “Letters on Brewing” says:

At the brewmasters’ convention in Pittsburgh in 1896, when the first few pages were offered for inspection, the whole assembly of brewmasters welcomed the book so heartilythat Dr. Ernst Hantke was encouraged to renewed activity. In 1897 at the brewmasters’ convention in Detroit, the first volume, comprising 668 pages, was ready for distribution in book form and 2 years later the second volume of 824 pages completed.

So Hantke was in the unique position to both have researched German brewing in scientific detail, but at the same time also witnessed large-scale beer production in the United States at the heart of American lager brewing. He discussed general differences, like the German preference of all-malt decoction mashing and the American preference of using adjuncts (unmalted grains) and infusion mashing. He even brought a specific rationalization for why this difference makes sense: decoction beers are more nutritious, but under the impression of the hot American climate during the summer, and the American habit of eating meat three times a day, it is easy to realize that customers will prefer a refreshing, pleasant-tasting, and fizzy drink to a nutritious one.

Also from a purely technological point he defended infusion mashing: he described American malts to be generally of high quality and usually kilned at low temperatures, so the available diastatic power was enough to reach the same level of extraction and efficiency as a decoction mash, but resulting in a more fermentable wort and a quicker process.

When I went through the book, I was especially excited to see descriptions of two mashing processes, one described as the “Wiener Maischverfahren”, the Viennese mashing process (essentially a 3 decoction mash with two thick and one thin decoction) as done by Schöneberger Schlossbrauerei from Berlin, while the other mash processes is the specific adjunct mashing process as practiced by Pabst. So not only contains this book general process descriptions of how German and American brewers were mashing, it even references the specific breweries that employed the respective techniques.

The descriptions were detailed enough to reconstruct the whole process and convert it to typical homebrewing sizes. The Viennese mashing process was first. The amount of beer produced 140 hectoliters, at an OG of 12° Balling (about the same as 12° Plato, OG 1.048). The amount of malt used was 2500 kg. So, to start scaling the whole recipe down to the typical homebrewer size of 20 liters, let’s see by which factor we need to scale it down. 140 hl / 0.2 hl = 700. Alright, then let’s convert the grist: 2500 kg / 700 = 3.571 kg. Wait… a 12° beer from just 3.571 kg of malt? That won’t work out, especially since the brewhouse efficiency is documented as 65.19 %. Something must have gone wrong there when the author transcribed the recipe or something. Nevermind, on to the second recipe, the Pabst adjunct mashing process.

In this process, 300 barrels of beer were produced from 10000 pounds of malt and 6000 pounds of grits. The grits are mashed in, boiled for 15 minutes, and then added to the main (malt) mash to raise the temperature to saccharification temperature. While we don’t know the exact OG of the wort that Pabst produced, another, very similar process mentioned in the paragraph right after the Pabst process, we can assume an OG of around 13.1° Balling (about the same in Plato, 1.053).

So, again for scaling: 300 barrels are 300 bbl * 117 l = 35100 liter. To scale down to 20 liters, we therefore need to divide by 35100 / 20 = 1755. 10000 pounds are 4536 kg, while 6000 pounds are 2721 kg, which means the grist consisted of 4536 kg / 1755 = 2.58 kg malt and 2721 kg / 1755 = 1.55 kg grits, in total a grist of 4.13 kg. To produce a 13° wort from just that amount of malt, you’d need to reach a high amount of extraction, especially so for home brewers, which I don’t think would be that easily doable with just an infusion mash. While slightly more believable than the numbers of the previous recipe, I’m still not quite sure whether this is 100 % correct or whether the author made a mistake of some sorts. Or maybe I made a mistake? I assumed 1 beer barrel to contain 31 gallons as is standard in the US (normally, 1 bbl contains 36 gallons), and I converted using US gallons (3.78541 liter), so my calculations should be sound.

Despite all these inconsistencies, we still learn valuable details: the grist of a late 19th century American lager as brewed by Pabst consisted of 62.5 % malt, 37.5 % corn grits, was mashed using an infusion mash with a separate adjunct mash/boil to gelatinize the grits, and the wort produced, if we can assume that most breweries at the time produced beer of about the same strength, was probably at an original gravity of about 13 °Balling (1.053). That’s a good start to formulate a recipe at least inspired by a lager of that era.

The mash process is also quite specific: dough in the grits into a liquor of 50 °C, the resulting mash should then have a temperature of 47.5 °C. Rest for 30 minutes, then heat up to 67.5 °C, rest for 20 minutes, then heat up to 75 °C over the course of 15 minutes. Then bring to a boil, and boil the adjunct mash for about 15 minutes. In the meanwhile, the malt is doughed in at a temperature of 45 to 47.5 °C. The adjunct mash is then added in two steps with 5 to 10 minutes inbetween, to raise the main mash temperature to 70 °C. From there on, the mash needs to convert the starches to sugar. When the mash is fully converted, the mash temperature is raised to 72.5 °C by adding more hot liquor, which concludes the mash. The first runnings of this mash should have an OG of 19° Balling (about 1.079). While not a complete recipe, with some additional calculation a homebrewer could work with that.

Compared to the adjunct infusion mash, the Viennese mash is more intricate: the 2500 kg of malt are doughed in so that the resulting mash is 92 hectoliters at a temperature of 17.5 °C. Then, 32 hectoliters of boiling water are slowly mixed in to bring the overall temperature of the mash to 37.5 °C. The first thick decoction of 30 hectoliters is then drawn and boiled for 30 minutes down to 26 hectoliters, then mixed back to the main mash to raise the temperature to 50 °C.

The next thick decoction, 40 hectoliters, is then drawn off, and boiled for 35 minutes down to 36 hectoliters. After mixing it back, the temperature of the main mash is at 61.25 °C. Then, the final decoction, 53 hectoliters of thin mash, are drawn off, and boiled for 35 minutes down to 49 hectoliters. After mixing it back, the main mash should be at a temperature of 75 °C, and the size of the mash in the mash tun should be 112 hectoliters. The whole process takes 4.75 hours.

After lautering and sparging, 152 hectoliters of wort are collected, which is boiled for 2.5 hours to get 140 hectoliters of wort at an OG of 12° Balling. The total work time for a single batch is described as 12.25 hours, surely a long brew day in Schöneberg, while Hantke mentions that brewing using the infusion method takes 5 to 7 hours, and not only saves time, but also lots of fuel that is otherwise required to boil the various decoctions.

So, what can we learn from this? First of all, always scrutinize historic recipes if it’s possible to check them for consistency (in this particular instance, we knew amounts of beer, grist, and OG). Second, we can still get a whole lot of information out of such historic records. We learned about the strength of American lager beer at the end of the 19th century, we learned about the grist composition in one particular instance, i.e. how Pabst used to brew their beer, and we even learned the specific method how Pabst used to conduct their mashes.

In my opinion, that is a whole lot to start developing a lager recipe: 13 °P, a ratio of malt and grits of 62.5/37.5, and mashed according to the infusion method described above. Hantke lists using about 1 pound of hops per barrel of beer for beers at 13° Balling. That’s a hopping rate of about 3.9 g per liter, which I find a bit too high, especially when using a classic American hop variety, such as Cluster. But then, with Cluster you should be able to achieve a bitterness and hop character that probably comes quite close to what American lager beer over a 100 years ago must have tasted like.

If you want to learn more about German-American brewing in the late 19th century (provided you can read German), here’s a link to the “Handbuch für den Amerikanischen Brauer und Mälzer“. For even more insight about 50 years later, there’s also the (English-language) “The Practical Brewer“, authored and edited in 1946 by the master brewers of Griesedick Bros. Brewery and Anheuser-Busch Brewery, both of St. Louis, Missouri. Even there, the great influence of Germans on American lager brewing is very noticeable, in particular in vocabulary.