Traditional German Sours
When I was getting ready to take the Beer Judge Certification Program (BJCP) test in 2007 I attended a pre-class run by my local homebrew club Brewers United for Real Potables (BURP). Each week the instructor would bring classic examples of the styles we were discussing for us to sample. One of the most memorable was an old bottle of Schultheiss Original Berliner Weisse. It was the last remaining Berliner weisse fermented with Brettanomyces. It was amazing how weird-citrusy-funky it was, yet bright and drinkable even at seven or eight years old!
These days it is difficult to buy a “plain” Berliner weisse or Gose in America. These two German relics have been relegated to the status of mere descriptors for a sour base ready for fruit, extracts, and other adjuncts . . . and the truth (in my opinion) is that is what the typical kettle soured versions deserve! These bland knock-offs are a shadow of the characterful historic styles. In Berlin even with assistance from a local, my wife Audrey was unable to get a glass of Berliner weisse without the neon-red raspberry syrup added.
Luckily, a handful of brewers in Germany, America, and elsewhere have revived the classic techniques. These can include mixed-fermentation, extended aging, no-boil, and bottle conditioning. The results are beers that shine on their own without the needed adornment of artificial syrups! The way the styles were intended.
There are plenty of articles about creating kettle-soured Berliner weisse and Gose, as this is the most common method these days; however, this article is going to discuss the traditional brewing methods that will take a bit longer to produce. The extra time will be well worth it, as the differences between the two approaches and resulting beers are significant.
Wort Production
One of the biggest issues with any low-gravity beer is a lack of base malt flavor. Not that Berliner weisse or Gose are known for rich or intense maltiness, but they shouldn’t taste watered down. Start by selecting a high-quality characterful Pilsner malt. Weyermann Barke® Pilsner is especially flavorful with a grassy-fresh malt character that I really enjoy. Wheat malt is traditional for both styles as well and adds a fresh “bread dough” note. To enhance foam texture, consider 5–15% under-modified chit malt or Carafoam®, especially if you are using a highly modified Pilsner malt. That’s it.
Mash to maximize fermentability: For a single infusion 146–148 °F (63–64 °C) or a step-mash 140–142 °F (60–61 °C) then 154–156 °F (68–69 °C). We’ll be packaging this beer relatively quickly, so avoid creating dextrins that the Brettanomyces will ferment, generating additional carbonation. No need for a ferulic acid rest as we are not trying to maximize spicy 4VG (4-vinyl guaiacol) production, as we might in other German wheat beers. A protein rest is optional, depending on the modification of your malt and your feelings about clarity.
We’ll rely on Lactobacillus for acidification, so I’d advise leaving hops out of the boil and mash entirely. Hops are antimicrobial, and Lactobacillus is the main “spoilage” microbe they inhibit. The typical 1–5 IBUs is below taste threshold and really won’t provide a significant benefit for the beer. Hop acids become increasingly toxic to gram-positive bacteria as the pH drops. As a result, with 5 IBUs you may see the acidification halt before your desired pH is reached. If you brew these styles frequently with the same Lactobacillus strain you may be able to dial in a hop dose that stops the acidification at your desired level.
After running off the wort, bring it up to 180 °F (82 °C). This is hot enough to pasteurize the wort and denature enzymes, while cool enough to not drive excessive conversion of S-Methyl Methionine (SMM) to Dimethyl Sulfide (DMS). I find the “no-boil” process preserves a fresh doughy maltiness that I like in Berliner weisse, but not Gose. After holding for 10 minutes, cool to 68 °F (20 °C) for fermentation. If you use an immersion-chiller you can heat the wort up to a boil if you’d prefer. This is what I did for years without issues. I visited a brewery that tried this process (based on my recipe in American Sour Beers) on their commercial system. However, the hour the wort spent just below 212 °F (100 °C) for whirlpool, settling, and running through their heat exchanger created an intense DMS character. They dumped the batch . . . and didn’t blame me too much! For Gose or a crisper Berliner weisse perform a full 60-minute boil.
Seasoning
While Berliner weisse is un-spiced, Gose is defined by the addition of coriander seeds. Just like you don’t see a recipe call for “hops,” I won’t call for just any coriander! The coriander you usually find in supermarkets has a citrusy-vegetal flavor that works perfectly for certain cuisines, but not beer. I prefer the flavor of the coriander from Indian markets. You can tell it visually by its rounder shape, think more futbol than football. The flavor is brighter, more like Fruit Loops® cereal. This is linalool, a common monoterpene alcohol also found in hops.
Linalool smells good, but certain yeast can convert it into beta-citronellol, which has a Sprite®-like lemon-lime aroma. This happens early in fermentation, so either add the coriander to the whirlpool, or directly to the fermenter (which I prefer).
Sodium is also a common feature of Gose. Adding table salt (sodium chloride) to the kettle is easy, but keep your addition to a minimum. It’s easy to add more to taste along with the priming sugar, but almost impossible to remove!
Fermentation
Despite Gose and Berliner weisse clearly being wheat beers from Germany, I don’t think yeast strains marketed as “German wheat beer” have a place. Traditionally, fermentation is cleaner without the banana (isoamyl acetate) or clove (4VG) notes of hefeweizen or dunkelweizen. If you want these flavors, that is up to you! I prefer either an American or German ale yeast, think Chico, Kölsch, or altbier. SafAle US-05 is my strain of choice because it is slightly fruity, attenuative, reliable, and not to
mention, inexpensive!
While different Lacto strains create slightly different flavors, primarily what you are looking for is lactic acid. In general, I prefer using more aggressive isolates, because there are options for stopping acidification (we’ll get into that in a bit). At Sapwood Cellars in Columbia, Maryland, we use Omega Yeast’s Lacto Blend, but most L. brevis and L. plantarum isolates will get the job done. See my article with Matt Humbard in BYO “Brewing with Lactobacillus” for more on these at https://byo.com/article/brewing-with-lactobacillus/. While yeast lab cultures can work well, probiotics can be a more readily accessible and cost-effective option. You can also culture the strains in yogurt whey or other dairy ferments. On a commercial scale we save money by propagating a homebrew-size pack up to 1–2% of the batch volume 24 hours in advance of brewing to ensure a quick start.
I love the complexity that Brettanomyces brings to these styles. I prefer fruitier (tropical, lemon, stone fruit) notes with a little funky/earthy. A bottle I had years ago of Bayerischer Bahnhof’s Berliner Style Weisse Brettanomyces Lambicus was a revelation. Highly acidic, with more funk than fruit. For our Berliner weisse at Sapwood Cellars, Little by Slowly, we sourced an isolate from Christophe Pinchon in France. He cultured it from an old bottle of Willner Brauerei’s Berliner Weisse (which went out of business in 1990). The only drawback of that strain is that young it is especially “dilly,” but given time it evolves into a beautiful “lemon-poppy” sort of aroma. We’ve had good luck with the lemony-mineral funk of The Yeast Bay’s Mélange blend as well. For our most recent batch we raided our barrel cellars and pulled 5 gallons (19 L) from a fantastic golden sour with an apricot note that we pitched directly into the primary.
Monitor the pH after pitching the ale yeast, Lactobacillus, and Brettanomyces. Once the pH drops to your desired level you can inhibit the Lactobacillus by adding a small amount of hop extract. We use an aqueous 20% alpha hop extract from Hopsteiner that adds no perceived bitterness. An isomerized alpha acid like tetra or hexa can work just as well with a target of 5–7 IBUs. Isomerized hop extracts are available from homebrew shops online if you can’t find them locally. As an added benefit, these hop compounds are foam-positive. A small dose of dry hops is another option, but may add an inappropriate hop aroma for the style.
Final pH will depend on your tastes, but that can be difficult to judge with the residual malt sweetness during fermentation. Coca-Cola® has a pH of 2.6–2.7 (thanks to phosphoric acid) but the sugar prevents it from tasting nearly as sour as a dry-finished Berliner weisse at a pH of 3.5. I prefer a finished pH of 3.2–3.4, more tart towards the high-end or more sharply acidic towards the low-end. You could go as high as 3.6 for very lightly acidic and 3.0 if you were planning to drink most of it blended or sweetened.
Packaging
High carbonation can make these beers difficult to serve on draft, so bottle conditioning is most common. Use heavy Belgian- or German-style bottles and aim for 3–3.5 volumes of CO2. For each 0.001 SG the Brett ferments in the bottle expect another 0.5 volumes of carbonation.
At the brewery we naturally keg condition, allowing backup kegs to sit warm to get more interesting and funky as time passes. The added advantage of a keg is that they are easier to vent-down if the beer is becoming over-carbonated.
Serving
These beers are delicious on their own, but they are also a fantastic base for additional flavors.
Especially if the beer ends up more acidic than you prefer, try dry hopping! This will raise the pH and add complementary flavors. I prefer citrusy and tropical varieties (pretty much anything you’d use in a hazy IPA works well here).
Fruit is an easy pairing — cherries, raspberries, apricots, etc. While you can add fresh fruit, we often use kegs of Little by Slowly to “rinse” the fruit leftover from barrel-aged sours. After having two or three oak barrels infuse on several hundred pounds of fruit there is still great flavor trapped in the fruit. One or two kegs of Berliner weisse on this fruit for even a few hours will pick up great flavor and color. You can do this at home by racking 1 gallon (4 L) of fermented Berliner weisse into a carboy or bucket that previously held a 5-gallon (19-L) batch of heavily-fruited beer.
If you want to get even weirder, the brewers at The Establishment Brewing Company knock out their cooled wort right onto the fruit and yeast from a previous sour. They brew a delicious Gose called Little Wing on second-use plums. This allows for longer contact and a more unique character.
The addition of syrups to Berliner weisse in Germany is more an end-around the Reinheitsgebot than a real necessity. However, if you enjoy the sweet-sour balance, it is an easy option for serving one without the need for pasteurization. You can buy the two standards: Himbeere (raspberry) and waldmeister (woodruff) at German specialty markets or on the internet. Another option is to make your own! Juices, soda syrup recipes, and cocktail mixers are all fun options to zhuzh-up a glass of Berliner weisse for a party, sour-reluctant friend, or yourself! Cambridge Brewing Company had a delicious one with plums and ginger when I visited years ago.
I started this article by poking fun at fruit and adjuncts making the kettle-soured version interesting, but adjuncts can take an interesting Berliner weisse or Gose and make them even more interesting! Here are a few of my favorites that we’ve created over last four years at Sapwood Cellars:
Berliner Weisse Variations
Little by Citra – Dry hopped with 0.5 oz. of Citra® hops per gallon (3.7 g/L)
Little by Sushi – White miso paste (for salinity) and pickled ginger
Little by Lemonade – Olio sacrum (lemon-oil saturated sugar) and fresh lemon juice
Little by Foraged – Fresh staghorn sumac
Little by Salted Apricot – Salt-fermented apricots (inspired by The Noma Guide to Fermentation)
Little by Smoothly – Fresh pineapple puree, lime zest, and cream of coconut
Gose Variations
Guava Salzig – Pink guava puree
Cucumber Salzig – Fresh cucumber juice
Salzig & Tonic – Aged in a gin barrel and then infused with lime zest and cinchona bark
Traditional German Sour Recipes
Sapwood Cellars’ Little By Slowly clone
(5 gallons/19 L, all-grain)
OG = 1.034 FG = 1.004
IBU = 6 SRM = 3 ABV = 3.9%
This Berliner weisse is one of the most characterful sub-4% ABV beers I have brewed. It combines acidity, bread dough wheaty notes, lemony-hay funk, and high carbonation. It is bright and refreshing like lemon-seltzer when consumed fresh and cold, but it is almost lambic-like when given extended cellaring and served at cellar temperature. The beer’s name is an oft-repeated line from Stephen King’s 11/22/63, and suggests the beer’s small size and slower fermentation compared to “quick sours.”
Ingredients
3.5 lbs. (1.6 kg) Pilsner malt
2.66 lbs. (1.2 kg) Weyermann wheat malt
0.9 lb. (0.4 kg) Best chit malt
88% lactic acid
1 mL HexaHop, TetraHop, or other isomerized alpha acid extract
Omega Yeast OYL-605 (Lacto) blend or Lactobacillus culture of your choice
Brettanomyces culture of your choice
SafAle US-05, Wyeast 1056 (American Ale), or White Labs WLP001 (California Ale) yeast
1–1.5 cups corn sugar (if priming)
Step by Step
Mash at 148 °F (64 °C), adding calcium chloride to achieve 150 ppm chloride. Add lactic acid if needed to achieve a mash pH of 5.2 Collect wort and heat to 180 °F (82 °C) for 10 minutes. Add lactic acid (approximately 10–15 mL) to achieve a pH of 4.4. Chill to 68 °F (20 °C), aerate, and pitch an active starter of Lactobacillus, yeast, and Brettanomyces. Allow to sour to a pH of 3.3 (or as desired), approximately 12–48 hours. Add isomerized alpha acid extract to arrest acidification.
Continue to ferment at 68 °F (20 °C). Approximate fermentation time in primary is one month. Once the gravity stabilizes, chill to 55 °F (13 °C). Transfer to a purged keg or bottle priming in Champagne-style bottles for as much CO2 as you are comfortable with (3–4 volumes).
Sapwood Cellars’ Little By Slowly clone
(5 gallons/19 L, extract only)
OG = 1.034 FG = 1.004
IBU = 6 SRM = 3 ABV = 3.9%
Ingredients
4 lbs. (1.8 kg) weizen dried malt extract
88% lactic acid
1 mL HexaHop, TetraHop, or other isomerized alpha acid extract
Omega Yeast OYL-605 (Lacto) blend or Lactobacillus culture of your choice
Brettanomyces culture of your choice
SafAle US-05, Wyeast 1056 (American Ale), or White Labs WLP001 (California Ale) yeast
1–1.5 cups corn sugar (if priming)
Step by Step
Starting with 5.25 gallons (20 L) water, heat to 180 °F (82 °C) then remove from heat. Stir in the malt extract until fully dissolved. Hold at this temperature for 10 minutes. Add lactic acid (approximately 10–15 mL) to achieve a pH of 4.4. Chill to 68 °F (20 °C), aerate, and pitch an active starter of Lactobacillus, yeast, and Brettanomyces. Allow to sour to a pH of 3.3 (or as desired), approximately 12–48 hours. Add isomerized alpha acid extract to arrest acidification. Continue to ferment at 68 °F (20 °C). Approximate fermentation time in primary is one month. Once the gravity stabilizes, chill to 55 °F (13 °C). Transfer to a purged keg or bottle priming in Champagne-style bottles for as much CO2 as you are comfortable with (3–4 volumes).
Tips For Success:
If getting pre-isomerized hop product is not possible, the alternate method would be to hold off pitching the ale and Brettanomyces yeast strains until after the souring process is complete (pH ~3.3). Once soured, heat the wort back up to 180 °F (82 °C), add a little bit of hops, then hold for 15 minutes before chilling back to fermentation temperature. Once chilled, then add both the yeast strains and follow the instructions found in the step by step.
Sapwood Cellars’ Salzig clone
(5 gallons/19 L, all-grain)
OG = 1.044 FG = 1.006
IBU = 7 SRM = 3 ABV = 5%
The coriander in this Gose provides a beautiful lemon-lime citrusy flavor that only adds to the refreshing qualities of this session beer. Spelt provides additional protein that improves body and head retention, but wheat malt in its place would also make a fantastic beer. Salzig means “salty” in German and rhymes with Leipzig, the town most associated with Gose.
Ingredients
5.25 lbs. (2.4 kg) Weyermann Barke® Pilsner malt
2.6 lbs. (1.2 kg) Weyermann spelt malt
1 lb. (0.45 kg) Best chit malt
0.5 oz. (14 g) Indian coriander
0.25 oz. (7 g) non-iodized salt
88% lactic acid
1 mL HexaHop, TetraHop, or other isomerized alpha acid extract
Omega Yeast OYL-605 (Lacto) blend or Lactobacillus culture of your choice
Brettanomyces culture of your choice
SafAle S-04, LalBrew Nottingham, or Imperial Yeast A01 (House) yeast
1–1.5 cups corn sugar (if priming)
Step by step
Mash at 148 °F (64 °C), adding 0.25 oz. of table salt and enough calcium chloride to achieve 150 ppm chloride. Add lactic acid if needed to achieve a mash pH of 5.2. Collect wort and boil for 60 minutes. Add crushed coriander and enough lactic acid (approximately 10–15 mL) to the fermenter to achieve a pH of 4.4. Chill to 68 °F (20 °C), aerate, and pitch an active starter of Lactobacillus, yeast, and Brettanomyces. Allow to sour to a pH of 3.3 (or as desired), approximately 12–48 hours. Add hop extract to arrest acidification. Continue to ferment at 68 °F (20 °C). Approximate fermentation time in primary is one month. Once the gravity stabilizes, chill to 55 °F (13 °C). Transfer to a purged keg or bottle prime in Champagne-style bottles for as much CO2 as you are comfortable with (3–4 volumes). You can add additional salt as desired to taste along with the priming sugar.
Sapwood Cellars’ Salzig clone
(5 gallons/19 L, extract only)
OG = 1.044 FG = 1.006
IBU = 7 SRM = 3 ABV = 5%
Ingredients
5 lbs. (2.3 kg) weizen dried malt extract
0.5 oz. (14 g) Indian coriander
0.25 oz. (7 g) non-iodized salt
88% lactic acid
1 mL HexaHop, TetraHop, or other isomerized alpha acid extract
Omega Yeast OYL-605 (Lacto) blend or Lactobacillus culture of your choice
Brettanomyces culture of your choice
SafAle S-04, LalBrew Nottingham, or Imperial Yeast A01 (House) yeast
1–1.5 cups corn sugar (if priming)
Step by step
Starting with 5.25 gallons (20 L) water, heat to 180 °F (82 °C) then remove from heat. Stir in the malt extract until fully dissolved. Hold at this temperature for 10 minutes. Add lactic acid (approximately 10–15 mL) to achieve a pH of 4.4. Chill to 68 °F (20 °C), aerate, and pitch an active starter of Lactobacillus, yeast, and Brettanomyces. Allow to sour to a pH of 3.3 (or as desired), approximately 12–48 hours. Add hop extract to arrest acidification. Continue to ferment at 68 °F (20 °C). Approximate fermentation time in primary is one month. Once the gravity stabilizes, chill to 55 °F (13 °C).
Transfer to a purged keg or bottle priming in Champagne-style bottles for as much CO2 as you are comfortable with (3–4 volumes). You can add additional salt as desired to taste along with the priming sugar.
Tips For Success:
If getting pre-isomerized hop product is not possible, the alternate method would be to hold off pitching the ale and Brettanomyces yeast strains until after the souring process is complete (pH ~3.3). Once soured, heat the wort back up to 180 °F (82 °C), add a little bit of hops, then hold for 15 minutes before chilling back to fermentation temperature. Once chilled, add both the yeast strains and follow the instructions found in the step by step.
