Author: Malcolm Frazer

I’ve been making sour mashed and kettle soured beers for a few years now. In addition to brewing and drinking such historic styles, I also really enjoy the initial research phase. There’s certainly nothing wrong with picking established recipes from trusted sources, but I consider the mystique, romanticism, and small connection to brewing history alluring. Those who have researched Berliner Weisse have likely encountered the same thing I have, namely what written history exists on the style is quite limited. Thankfully, folks like Ron Pattinson from Shut Up About Barclay Perkins and the incredibly dedicated Milk The Funk group have done a lot of digging, arming interested brewers with inspiring information about how to make these delicious styles.

There are many variables brewers have to consider when making Berliner Weisse or any other sour ale that gets its primary character from lactobacillus, many that never come into play with traditional brewing practices. For example, which of the numerous souring methods to use or whether to purge with CO2 during the souring phase. Another variable that has gotten a lot of focus lately has to do with post-souring wort managing, specifically whether or not it should be boiled prior to yeast being pitched. In my exploration of the original Berliner Weisse, I found it was commonly described as having a doughy and fresh bread character, which some have speculated is a function of not boiling the wort, a practice others warn could bring about the DMS boogieman or leave the beer tasting of raw uncooked wort.

| PURPOSE |

To evaluate the differences between two Berliner Weisse beers of the same recipe where one was boiled for 45 mintues while the other was not boiled at all.

| METHODS |

I went with a pretty typical Berliner Weisse recipe for this xBmt, a style I’ve come to use no hops in at all.

Berliner Weisse

Recipe Details Batch Size Boil Time IBU SRM Est. OG Est. FG ABV 5.5 gal 45 min 0.0 IBUs 2.7 SRM 1.034 1.007 3.5 % Actuals 1.034 1.007 3.5 % Fermentables Name Amount % Wheat Malt, Ger 3.25 lbs 50.49 Barke Pilsner (2 Row) Ger 3 lbs 46.6 Munich 10L (Weyermann) 3 oz 2.91 Yeast Name Lab Attenuation Temperature Ultimate Flora Probiotic 72% 64°F - 69°F SafAle German Ale (K-97) DCL/Fermentis 73% 59°F - 75.2°F

My brew day began like most others with water collection then, while it was heating to strike temperature, gathering and milling of the relatively small amount of grain.

Since the variable wouldn’t be introduced until later on in the process, I performed a single large mash in order keep things as consistent as possible between the batches. With the strike water ready, I mashed in to hit my target temperature and let the mash rest for 60 minutes before collecting the entire volume of sweet wort into another cooler MLT. The also took a hydrometer measurement at this point that confirmed I hit my target.

From here, I used a heat stick to bring the wort to 170°F/77°C for pasteurization.

Once pasteurized, I used my immersion chiller to drop the wort to my preferred souring temperature of 95°F/35°C. As a matter of course, I pre-acidify the wort to around pH 4.5 ±2 when quick souring, not only for the purported foam stability benefits, but because it lessens the overall souring time thereby reducing the potential for unfavorable microbes to take hold.

I opted not to purge the souring vessel beforehand or blanket the wort with CO2 prior to pitching the lactobacillus, which in this case was in the form of an over-the-counter probiotic. Based on what I’ve read and personal experience, I aim for 80-100 billion cells of lactobacillus per 5 gallon batch of Berliner Weisse wort.

While each probiotic capsule contains 90 billion total cells, only 54 billion of those are lactobacillus, so in order to reach my target pitching rate, I sprinkled the contents of 4 capsules directly onto the surface of the wort.

The insulated souring vessel was wrapped in blankets and left alone in my garage. At 18 hours, I found the wort had dropped to pH 3.3, perfect!

Another hydrometer measurement at this point revealed little change to the OG.

The time had finally come to introduce the variable. I started by transferring equal portions of the soured wort to either a fermentor or boil kettle, alternating between them for purposes of homogeneity. I then placed the kettle on my burner and brought the wort up to a rolling boil, leaving it there for 45 microbe murdering minutes.

Once the boil was complete, I quickly chilled the wort to 68°F/20°C before adding approximately 1.5 liters of filtered water to equalize the OG between the batches, as we wanted to avoid that being the reason for any perceived differences.

The carboys were placed in a tub of cool water and the beers allowed to ferment in a corner of my garage that maintains a steady 68˚F/20˚C this time of year.

Active fermentation was observed the following day, about 18 hours after pitching the yeast. With such a low OG, fermentation was complete by day 3, but I let the beers mature for a few more days before taking hydrometer measurements indicating both had reached a similar FG.

However, a pH measurement at this point revealed a difference that seemed like it could potentially have a qualitative impact.

Forgoing cold crashing and fining with gelatin, I transferred the finished beers directly to kegs.

I burst carbonated the beers overnight then reduced the CO2 to serving pressure for a few days before I began collecting data. While slight, the color difference I noticed following the boil seemed to carry through in the finished beers.

| RESULTS |

A panel of 37 people with varying levels experience participated in this xBmt. Each blind taster was served 2 samples of the no-boil Berliner Weisse and 1 sample of the boiled Berliner Weisse in differently colored opaque cups then instructed to select the unique sample. At this sample size, 18 tasters (p<0.05) would have had to accurately select the unique sample to achieve statistical significance. Ultimately, 31 tasters (p=0.0000000004) chose the different beer, suggesting participants were able to reliably distinguish the boiled Berliner Weisse from the no-boil sample.

The 31 participants who correctly selected the unique sample in the triangle test were then instructed to complete a brief preference survey comparing only the two different samples, all still blind to the variable. In the end, 15 tasters reported preferring the boiled sample, 13 said they liked the no-boil version better, and 3 people had no preference despite noting a difference between the beers.

My Impressions: As I imagine most brewers do, I began sampling these beers when taking gravity samples and was pretty sure I noticed a difference at this point. The no-boil beer had a distinct aroma of fresh doughy wort, which I found pleasant, in addition to a cabbage-like sulfur with minor tart cheese reminiscent of isovaleric acid, which was not very pleasant. The difference settled out some degree after fermentation was complete, but they were still easily distinguishable to me. Over multiple attempts, both administered to myself and by others, I was able to identify the different beer every single time.

| DISCUSSION |

Over the years, I’ve had numerous Berliner Weisse beers, some boiled and others not boiled, but this is the first time I’ve been able to sample them next to each other. In addition to my personal experience sampling these beers and being able to easily tell them apart, the fact participants were able to reliably distinguish them supports the notion that post-sour boiling has a qualitative impact on the finished beer. I suppose this comes as no huge surprise given the understanding that certain organisms the boil is intended to remove continued working in the no-boil beer.

Perhaps more compelling is the preference data showing that about half preferred the no-boil beer while another half liked the boiled batch better. As someone who has been homebrewing for almost two decades, I’ve know what it’s like to rely on the opinions of others to inform my brewing decisions. These xBmt results reminded me that, while deferring to trusted sources can certainly help make me a better brewer, trying various methods out for myself is the only way to dial in the approach that works best for me.

Please feel free to share your experiences making quick sour beers with or without boiling in the comments section below!

Support Brülosophy In Style!

All designs are available in various colors and sizes on Amazon!

Follow Brülosophy on:

If you enjoy this stuff and feel compelled to support Brulosophy.com, please check out the Support Us page for details on how you can very easily do so. Thanks!

Advertisements

Share this: Facebook

Twitter

Pinterest

Tumblr

Email



Like this: Like Loading...