Tag Archives: berliner weisse

The Diversity of Beer, 200 Years Ago And Now

You’ve probably heard the complaint before: craft beer is becoming monotonous, it’s all about IPA, most breweries just brew hazy bois with a few fruited sours and pastry stouts sprinkled in between, and if they feel extra special, a West Coast IPA. This is usually refuted with the argument that brewers just brew what pays the bills, it’s what people want to drink, etc., which is again countered with lamentation that other beer styles are dying out (ok, a bit hyperbolic) because nobody brews them anymore.

This is not a new phenomenon.

150 to 200 years, German beer and brewing experienced a massive shift. Small breweries were previously mostly brewing relatively small amounts of beer solely for the local market using little to no automation, brewers were organized in guilds, not interested in scaling out their businesses, and sometimes even bound by local law to brew and sell their beer on a rota (Reihebrauen). Then the industrial revolution came and destroyed a lot of these structures.

In some cases it was young brewers with an entrepreneurial spirit taking over from their fathers and looking to expand and grow it using modern technologies, in others it was simply trained brewers backed by money to start entirely new brewing companies with all the latest equipment and scientific knowledge to brew excellent beer.

Bottom-fermented beer became fashionable, and due to how it was produced and stored (at cold temperatures with a yeast that increased the sulphur content of the beer, two factors contributing to a more stable beer) the beer became more suitable for export. Export in this context simply meant shipping it further than what was the common “local” area, but innovations like the railroad made it possible to ship beer quite a bit further, and with the invention of ice waggons, some breweries were even able to establish proper cool chains (a famous example for that is the Dreher brewery in Kleinschwechat near Vienna which shipped ice-chilled lager beer from their brewery to the Paris Expo 1867, one delivery took just 5 days and was kept at a constant 4°C). The beer tasted clean, fresh and properly quenched the thirst of beer drinkers.

People started craving this fashionable beer, so naturally, the market adjusted to it, beer legislation was liberalized, and more brewers had the opportunity to enter the market and brew bottom-fermented beers. At the same time, the old-time breweries where “local beer for local people” had been brewed for hundreds of years, didn’t have the money to upgrade their equipment to brew these new-fangled beer styles, or even to make smoke-free malt like the new lager breweries were doing it.

Within just a few decades, a lot of small, local breweries simply shut down because they couldn’t compete, and local beer styles (German brewing literature at the often spoke of Lokalbiere) simply went extinct because nobody wanted to drink them anymore. A lot of these beers we only know by name these days, a few have been preserved in the form of recipes, though a lot of details like how specific malts were prepared are not so well documented, leaving more questions than answers.

When we look at Germany, which beer styles are prevalent (because craft beer is really just a teeny tiny 1% segment of the whole market) and which of these beer styles are from before the industrial revolution, it becomes apparent how bleak it really is.

To the best of my knowledge, the list is really short: Berliner Weisse, Bavarian Weißbier, Altbier and Kölsch (I like to group them as Rhenish Bitter Beers or Top-Fermented Lager Beers because they are more similar than different though people from Düsseldorf and Cologne may hate me for that), Leipziger Gose, and Bamberger smoked beer, and some of them did not fare too well in the last 70, 80 years and were only just rescued from dying out.

Berliner Weisse was still brewed by a few breweries in both East and West Berlin after World War 2. The biggest shock was probably when Schultheiss stopped brewing their traditional unboiled mixed-fermented version. Berliner Kindl Weisse, a very industrial beer brewed by fermenting a low-alcohol beer normally and blending it with another batch that was just fermented with lactic acid bacteria and then sterile-filtrated, thus became the only available brand on the market. In Berlin, the style was really only rescued by a few craft brewers, such as Andreas Bogk, BrewBaker, Lemke, Schneeeule, Berliner Berg, Vagabund, and others, who specifically intended not to let this piece of beer history die out.

Bavarian Weißbier was already a niche product when it again became permitted for private Bavarian brewers to brew with wheat again, and it only survived because of a relatively small group of connoisseurs, until the 1960s when it suddenly somehow became more fashionable again and thus had its revival.

Altbier and Kölsch were not particularly popular during the interwar period, and really only regained popularity after World War 2: Kölsch as it was marketed as a genuinely local beer, appealing to the hyperlocal patriotism in Cologne, while Düsseldorfer Altbier apparently only regained popularity in the 1960s. Münstersches Altbier, another Altbier style, really only exists in the form of one brewery, Pinkus Müller.

Leipziger Gose was actually functionally extinct from the early 1960s when the last Gose brewery shut its doors until the mid-1980s, and it could only be rebrewed and revived to its original taste because the East German brewers producing it could have it taste-tested by beer drinkers who still remembered it from before the 1960s.

And finally smoked beer. Even in Bamberg, this is kind of a niche product. Of the more than 10 breweries that are still around, only two still make their own smoked malt to brew their very own smoked beer, Brauerei Heller (Schlenkerla) and Brauerei Spezial. Greifenklau stopped their own kilning operation in the early 1970s, but fortunately is still around. Nowadays, they brew some smoked beer as a seasonal product, but their owning malting and kilning operation is long gone. And Polarbär brewery, which I like to call the fourth Bamberg smoked beer brewery isn’t operational since the 1950s or so.

And yet, none of these beer styles are truly extinct or even remotely in danger of going extinct. Why? Simply put, thanks to craft beer. Starting in the US, but now really all over the world, there are countless beer nerds who truly care about these old beer types, some rebrew them at home, others brew them commercially, making these beers that were definitely at the brink of extinction better known to beer drinkers all around the world.

Yes, there is some truth that IPAs and hazies are taking over, and yes, some breweries certainly struggle with that problem, because it’s what pays the bills. “The customer is king”, and it would not make sense economically to brew a beer that would not be as popular and thus not sell as well. In the end, IPAs keep the other styles afloat, as the money earned through them gives brewers some freedom to also try out other styles. Styles that used to extremely local to just small regions of Germany have now gained worldwide fame. Even 50 years ago, this probably would have been mostly unthinkable.

Experiment Time: Does Lactic Acid Skew Refractometer Readings?

In a Facebook group I follow, an interesting problem came up. Somebody had brewed a mixed-fermentation Berliner Weisse with brewer’s yeast, lactobacillus brevis and brettanonymces claussenii. They didn’t own a saccharometer, but instead determined their OG with a refractometer. They now wanted to know whether fermentation was finished, and used the refractometer as well to measure the beer that had been in the fermenter for several weeks.

Before I continue, a quick excursion into how refractometers work. Every translucent material bends light to a certain extent, the light gets refracted. To describe the extent with which the light is bent, the so-called refractive index is used. The refractive index n is defined as n = c / v, where c is the speed of light in a vacuum, and v is the speed of light in the particular medium. Water for example has a refractive index of 1.333. When we dissolve sugar in water, the refractive index of the solution is increased. The refractive index of a 10% glucose solution in water is 1.347, for example. This change in the refractive index can be used to indirectly measure the OG, by looking at the difference between the expected refraction of water vs the measured one, i.e. by how much more light gets refracted.

In fermented beer, this gets trickier, because due to fermentation, the resulting liquid contains ethanol. Ethanol has a refractive index of 1.361, which skews the overall measurement. Ethanol also skews the measurement when determining the FG of a beer, as its specific gravity is just 0.79. In typical fermented beers, the amount of ethanol is large enough that we need to correct our measurements to be able to estimate the actual FG. This is all fine.

The mixed fermentation opens up another problem, though. It has a refractive index of 1.427 which significantly higher than that of either water or ethanol, but in typical fermented sour beers, its content by weight is fairly low compared to e.g. ethanol. According to this presentation, typical Berliner Weisse contains 2 to 4 g/L of lactic acid, i.e. 0.2 to 0.4% by weight.

When I read about the issue of seemingly underattenuated Berliner Weisse, one of the things that came to my mind was exactly whether the lactic acid from the mixed fermentation skewed the measurement enough to cause such a large disparity that a beer that is expected to be overattenuated to come up with an apparent attenuation of just 68%.

So I asked myself the question: if I added the typical concentration of lactic acid in a Berliner Weisse (i.e. 2 to 4 g/L) to distilled water, by how much would my refractometer be skewed?

I have a refractometer at home, 2 litres of distilled water, a big bottle of 80% lactic acid, and pipets with which I can measure out millilitres of lactic acid. But how many grams is a millilitre of lactic acid? A millilitre of pure lactic acid weighs 1.357 grams, therefore a millilitre of an 80% solution would weigh would weight about 1.285 grams. Since I want to test a whole range of lactic acid content, just measuring out by ml is good enough for me.

I poured 1 litre of distilled water into a clean vessel, and calibrated my refractometer so that it shows exactly 0°Brix. I then added 1 ml of lactic acid (= 1.285 g), stirred it well, and measured again with the refractometer. I measured X°Brix. I then repeated this to up to 5 ml of lactic acid (= 6.425g), and got the following measurements:

  • 1 ml (~ 1.3g): 0°Brix
  • 2 ml (~ 2.6g): 0.2°Brix
  • 3 ml (~ 3.8g): 0.4°Brix
  • 4 ml (~ 5.1g): 0.4°Brix
  • 5 ml (~ 6.4g): 0.6°Brix

This was actually less skew than what I had expected. For a quick counter-check, I added 80% lactic acid on the refractometer, and the measurement was off the scale.

Luckily, I have a Berliner Weisse maturing at home. I brewed it a few months ago, mixed fermentation with S-04, Lacto brevis and Brett bruxellensis. I simply lautered and sparged 30 litres of wort from a 50% Pilsner/50% pale wheat malt mash, which turned out at 11°P OG (unboiled, of course). On my refractometer, I measured 5.2°Brix, while with my saccharometer, I measured 2.0°P. I used calculators to get the expected attenuation based on the OG (in Plato) and FG (in Plato) resp. refractometer reading (in Brix). For both values, I got almost the same level of attenuation (81.82 vs 82.11 apparent attenuation) as well as almost the same ABV (4.7% vs. 4.72%). This is fairly consistent with what I’ve measured earlier, namely that the amount of lactic acid in Berliner Weisse has very little impact to skew a refractometer measurement.

Nevertheless, I think it goes without saying though that a brewer should never ever rely on a refractometer alone. While I use one during my home-brewing, I only ever employ it to measure sugar content ad hoc during the brew day: it’s useful to observe saccharification of your mash, the strength of your first runnings, as well as the sugar content in your final runnings, or to get a good idea about the pre-boil gravity and post-boil gravity of your wort. It’s a tool that has its place, but for observing the progress of fermenting beer, I think it’s a much better idea to just use saccharometers. Even quite precise ones, with a scale down to 1/10 of a degree Plato, and thermometers for further correction of the measurement, are not exactly expensive.

How to Brew my Award-Winning Berliner Weisse

I recently brewed a Berliner Weisse, submitted it to SLOSH SOUR 2019, a homebrewing competition dedicated to Berliner Weisse, and I won! So here I’m documenting how I brewed and what’s the rationale behind it.

Since the homebrewing competition was about brewing straight Berliner Weisse, with no twists and no innovations, I decided to simply follow how Berliner Weisse used to be brewed according to historic brewing literature.


Naturally, I wanted to use large amounts of pale wheat malt. Historically, the wheat malt used in Berliner Weisse was high in protein and quite undermodified. Malt like that is practically impossible to get, so instead, I chose to use a large amount of chit malt. To bulk the grist up a bit more, I also added some floor-malted Bohemian Pilsner malt. The final grist looked like this:

  • 2 kg pale wheat malt (Weyermann)
  • 1 kg chit malt (BEST)
  • 0.5 kg floor-malted Bohemian Pilsner malt (Weyermann)


Berliner Weisse is classically mash-hopped, so I simply added 6 g of Tettnanger hops (3.4% alpha acid) to the mash.


I mashed in all the malt with 10 liters of hot water. To stay authentic, I used untreated Berlin tap water. I slightly underestimated the required temperature, so the resulting mash temperature was 46°C. I then heated it up to 53°C and did a protein rest of 40 minutes.

I then heated up the mash up to 62°C, and did a brief saccharification rest of 15 minutes, then further heated it up to 72°C to rest and convert for 45 minutes. After these 45 minutes, the mash was completely converted.

Now this is obviously a weird mash schedule, but in fact I based it on the mash schedule documented by the former Groterjan brewmaster A. Dörfel. At Groterjan, an initial protein rest was done at about 53-54°C, then the mash was slowly heated up to 75°C. I did a brief 62°C rest because I assumed that on my homebrew kit, heating up would be much quicker than on Groterjan’s big kit. I also kept the temperature a bit lower to prevent any issues from potentially overshooting the target temperature. I also left out one step that Groterjan did: they boiled parts of the mash as a final step and slowly mixed it back, trying to keep the temperature at a maximum of 76°C. This just did not make sense for me to do on my homebrew kit.

After conversion was finished, I moved the mash to my lauter tun, briefly did a lauter rest, and then started lautering and sparging. I collected about 20 liters of wort, which I then brought up to 80°C to pasteurize it for 10 minutes. I then chilled the wort down to 20°C and pitched all my microorganisms.

Yeast and Bacteria

I pitched half a sachet (5g) of S-04 dry yeast, a pack of White Labs WLP672 Lactobacillus brevis and a pack of White Labs WLP650 Brettanomyces bruxellensis at the same time, and let it ferment together.

If you want to recreate this and are worried about infections: my protocol is to simply have a separate fermenter for anything involving Brett and Lacto fermentation, that hasn’t caused me any issues in the past.

Primary fermentation quickly started and was finished after about 3 days. The souring process took a bit longer, but after about 3 weeks, the young beer had attained a good acidity. Around the same time, a secondary fermentation, presumably from the Brettanomyces kicked off, which was done after about a week. I then let the beer sit in the fermenter for another few weeks, and then bottled it. As priming sugar I used common sugar, and went for a carbonation level of 6 g/L. Then I put all the bottles in a quiet corner and let it mature.

The OG of the beer was 8.8°P (1.035), slightly higher than the 8°P I had actually planned. At bottling time, the FG was measured to be 0.8°P (1.003). The calculated amount of alcohol is therefore 4.2% ABV. A bit higher than what I wanted to go for, but still low enough to make the beer low and refreshing.

At the time of the competition, the beer was about 2.5 months old, so still fairly young. According to one taster who described himself as hypersensitive to sulphur, it still had some hints of sulphur left. The overall flavour and aroma was quite pleasant though: tart, citrusy, but not overly sour, so that the beer was still balanced and refreshing.

I still have a few bottles left, so my plan is to keep some of them and age them for longer. This should definitely help the Brettanomyces develop more complex and interesting flavours. I also kept the yeast from the bottom of the fermenter, and I plan to repitch it in future batches. I’m actually thinking about brewing another Berliner Weisse soon, just to have something to age and maybe hand in for next year’s SLOSH SOUR competition.

Thanks to everyone involved, in particular THE MASH PIT who organized the homebrewing competition, and Berliner Weisse Kultur e.V. who made it possible for me to present my home-brewed beer to a wider audience at Berliner Weisse Gipfel.

Berliner Weisse Summit 2019

Berlin is one of those places that have a rich brewing history, not just because of literally hundreds of breweries that used to brew beer all around the city, but also because it’s home to one of the few old German beer styles that have survived to this day.

While the style was neglected in the second half of the 20th century, and had a hard time to keep its place in Berlin’s beer landscape, the recent surge in interest through the craft beer movement has helped repopularize it. When a few years there were only a few breweries like Brewbaker and Bogk Bier that restarted brewing the style the traditional way, this has changed: with local breweries like BRLO, Vagabund, and Berliner Berg, the landscape of locally brewed Berliner Weisse has expanded dramatically.

The rise in popularity also shows in the beer festival landscape: 6 years ago, Sylvia Kopp initiated the Berliner Weisse Gipfel (Berliner Weisse Summit in English), a beer festival centered about Berliner Weisse, but it’s also open for other “wild and sour” beers. On June 1, the fifth edition of this beer festival (now organized by Berliner Weisse Kultur e.V.) took place, and the number of breweries visiting and exhibiting their beers has been even greater than in the years before. And not just from Berlin, but breweries from all the over Germany as well as the Netherlands and even the US took part.

There were too many beers to try, but some of my highlights were:

  • Berliner Berg Schiller Weisse, very refreshing and easy drinking, exactly how it should be as a summer beer. Cristal Peck, Berliner Berg’s brewmaster, is incredibly enthusiastic about the style, and seems to be doing plenty of experimentation to get the beer just perfect.
  • Schneeeule Marlene. Less sour than some might expect, but with plenty of funk. A great beer to age.
  • Nevel from the Netherlands brought two golden sour ales, one called Alm seasoned with “forgotten herbs” which they forage themselves, and another one called Minne which was seasoned with Japanese flowering quince. Very complex, very balanced, quite refreshing even at 5+% ABV.
  • Oedipus, also from the Netherlands, brought a few of their sour beer creations, which so far have always been great, and this year was no exception.
  • Felix from Orca Brau brought an unboiled Berliner Weisse of 14 months age as well as Bretted Brokantie, a bretted version of his farmhouse ale. Both beers were good on their own, but what stood out was that Felix also offered pouring blends, and it worked: a shot of his Berliner Weisse added to Bretted Brokantie really brightened it up.
  • August Schell from New Ulm, Minnesota was there with a few versions of their Berliner Weisse. I tried Ulmer Weisse, their version of American Weissbeer, an obscure American version of Berliner Weissbier that is mentioned in the 1901 book American Handy-Book of the Brewing, Malting and Auxilliary Trades. It worked beautifully, and I’m so glad that they revived this historic beer style and also brew traditional Berliner Weisse in a historically pretty authentic way. Jace Marti, August Schell’s assistant brewmaster, also did a presentation on how they brew Berliner Weisse, and he recently also recorded a podcast about the same topic.
  • Joe Stange brought bag-in-box Den Herberg Oude Lambiek, which was a real treat.

There were so many more breweries, but I couldn’t try them all.

Besides just visiting the beer festival, I also had the privilege of serving my own Berliner Weisse. This year, THE MASH PIT together with Berliner Weisse Kultur organized a homebrewing competiton just for Berliner Weisse, SLOSH SOUR. Since I wanted to get more into Weisse brewing, this was a great chance for me to take part. Unfortunately, it was a bit of a short notice period, so apparently one four or so people registered, and my beer was the only one that was actually submitted. The jury sampled the beer, and found it to be good, so I won the competition and could serve the beer to festival visitors. It was well received, and someone even took the time to add the beer on untappd!

All in all, I’m very happy this beer festival exists, and it’s become my favourite one in Berlin. This has been by far the most communicative, enthusiastic, exciting, and totally nerdy beer festival here in Berlin, and I’m especially glad about it because it’s one important part of the effort to keep this historic beer style alive.

An Outlandish Theory about Northern German White Beers

Since I started researching for my first e-book, I read quite a few things about white beers that were brewed in Northern Germany, and I noticed some similarities, not primarily in the ingredients, but in how the beers were described and compared.

Let’s start with the archetypal Northern German white beer, Broyhan. It is said that it was first brewed in 1526 in Hanover by a brewer named Cord Broyhan or similar. Said brewer had learned his trade in Hamburg, and then went back to Hanover to brew beer like in Hamburg. But allegedly, the brew didn’t quite work out, and the beer turned out to be different, but still tasty, so it was swiftly sold under the brewer’s own name. Most likely, Cord Broyhan wanted to brew Hamburger Weissbier. Now what was the difference between Hamburger Weissbier and Broyhan? We don’t know. The sources don’t say. But we can safely assume the beers must have reasonably similar. Maybe the malt was treated differently, maybe the local water had an influence, maybe the local brewer’s yeast yielded different results, maybe the brewer simply forgot to acquire hops (Broyhan is said to have been brewed without hops). But what we do know is that it was a slightly sour beer style.

The next one is Kottbusser Bier, a beer style from Cottbus. Several sources describe it as white beer “like Broyhan, but with hops”. Typical recipes include various malts in different ratios, all of them air-dried, then usually sugar, and sometimes honey, as well. Hopping rates suggest a very restrained or even unnoticeable bitterness, and no hop aroma whatsoever. Historic sources also confirm that it definitely was a sour beer.

Then there’s Berliner Weisse. It’s made from pale malts (which used to be air-dried), and it’s sour. The sourness was something that was only established in the 18th century through the introduction of yeast from Cottbus breweries. Interestingly, Berlin brewers had to constantly renew their yeast through new shipments from Cottbus, as the mixed fermentation culture was not stable and caused too much sourness when repitched several times. It also means that Berliner Weisse and Kottbusser Bier shared a common character through the yeast and the lactic acid bacteria, while also having a relatively similar grist. And then there’s this historic source from the 18th century that describes the production of Berliner Weisse and contains an interesting formulation: the wort was made without hops, while a separate hop extract was produced, and this extract was added to the Breihan (merely a different spelling of Broyhan), which in this context clearly refers to the unhopped wort. It’s unclear whether Broyhan was a generic term for any unhopped beer, or whether Berliner Weisse was brewed just like Broyhan at that time, the main difference being the addition of hop extract.

And finally, Gose. Nowadays, Gose is brewed with coriander and salt, and is also slightly sour, but historic sources mention nothing about coriander or salt, but do describe it as sour, in one instance even as essentially being the same as Broyhan.

And that’s how my outlandish theory is formed: since several historic sources describe close relationships between Broyhan, Kottbusser Bier, Berliner Weisse and Gose, either in taste or in ingredients, I think that this is a indicator that these four beers are the same beer style, or to be more specific, the respective local expressions of beer with a specific aroma, flavour and colour. Despite a certain difference in ingredients, the similarities were recognized, and so the beers satisfied the customers’ expectations of sour white beer. Each were individual in their own ways, but each would very likely be in such a condition that they could replace any of the other beer styles of that group and still meet the expectations of beer drinkers. And all four beers are representative of a beer fashion that dates back about 500 years ago.

That being said, there is a reason why I titled this theory to be outlandish. It is based on conjecture, riddled with assumptions, and probably too good to true. Nevertheless, whenever I read about the sour white beers of Northern Germany, I get the feeling that they’re just so similar to each other, almost like they’re related. In some ways, I want it to be true, but then, there is no way to prove such a strong relationship. And finally, there is another question that remains completely unanswered: whether there was any relationship between Northern German white beers and Belgian lambic or gueuze.

Brewing a Historic Berliner Weisse

It’s March, and I’ve been wanting to brew a Berliner Weisse for quite a while. So what better time to brew a Märzen-Weisse?

Relatively little is actually known about Märzen-Weisse. What is known is that it’s a stronger version of a regular Weisse. In his 1947 brewing notes, the brewmaster of Groterjan brewery mentioned a high-gravity version of 16-18 °P that some breweries produced occasionally. I don’t know whether that’s the Märzen-Weisse strength, but it definitely sounds intriguing.

For this brew, I teamed up with Franz Pozelt of Slowfood Berlin, to do one Weisse according to my recipe, and then one Weisse according to his recipe. Last Sunday was the first of two brewing dates.

We started off with a historic Berliner Weisse recipe that calls for 20 parts pale barley malt, 10 parts wheat malt, and 2 parts oat malt. We didn’t know where we’d end up in terms of gravity (because it’s a no-boil recipe, see below), so we used 4 kg Pilsner malt, 2 kg pale wheat malt, and 400 g oat malt.

The mash schedule was also based on historic methods: with dough-in at about 40 °C, we then slowly rose the temperature until we reached 50 °C to rest for 15 minutes. Then we continued to slowly heat up until we reached 62 °C, which we held for 45 minutes. We then drew a thin decoction and boiled it for about 5 minutes. At this point, we also added the hops, literally 3 leaves of Hersbrucker, to boil it. Mash hopping is another historic method in Berliner Weisse.

We then mixed the decoction back to raise the temperature to 72 °C, held that temperature for another 15 minutes, and then moved the mash to the lauter tun. With enough vorlauf to achieve a bright and clear wort, we then went on to sparge. Since this was going to be a no-boil Berliner Weisse, we didn’t know what efficiency to expect, so we simply collected enough wort until we reached 16 °P.

The wort was then heated up to 95 °C, and the temperature held for 20 minutes. This was a bit of a compromise, as older recipes lauter directly to the cooling tub resp. the fermentation vessel, but the Groterjan brewmaster mentions this as a possibility to prevent beer infections (such as Pediococcus) without having to resort to a boil. Interestingly, the resulting wort had 17 °P. That may be due to a measurement error earlier, and we didn’t mix the wort properly before (my experience is that during lautering, the runnings don’t mix well, most likely due to different specific gravity, so you get wildly different measurements with the refractometer depending where you take your sample).

Right after that, the wort was transferred to the fermentation vessel, and cooled down to 30 °C.

Fermentation itself is where my approach deviates from history: to better control the resulting sourness, I decided to sour the wort with a big starter of Wyeast 5335 Lactobacillus buchneri, and when sourness will have approached a good level, yeast will be pitched. I decided for US-05, as it’s a relatively neutral ale yeast which has been shown to successfully ferment even in wort with a pH level of 3.38, plus it’s cheaper for me to get several sachets of it than e.g. a single vial of WLP029 or a smack-pack of Wyeast 1007.

Since the brewday went without any issues, the lacto is doing its work now, and I’ll keep measuring the pH levels and tasting the souring wort. The yeast will be pitched when the sourness is right. In addition to that, the fermentation vessel was used to ferment and mature a batch of porter with Brettanomyces, so I expect an infection with B. claussenii, as well, which is perfectly fine for the style.

I’ll report about any results. At the moment, the lactobacillus is slowly fermenting away, producing some CO2. I suppose that’s fine, as L. buchneri is heterofermentative.