Alternative Bacteria Sources

Sources for Lactic Acid Bacteria, especially Lactobacillus, are available in various forms such as unpasteurized products and probiotics. This page contains a list of sources that Milk The Funk members have experimented with, and their results. Note that the production of products such as probiotics may not be as sanitary as brewing industry yeast manufacturers, so without isolating these bacteria on agar plates, they can not be considered pure cultures. Methods contained on this page use only materials that a typical homebrewer would have on hand and are geared towards brewers without agar plating capabilities. For information on isolating pure cultures of Lactobacillus with selective media on agar plates, see the Lactobacillus and wild yeast isolation pages.

Yogurt Souring

Mike Karnowski from Green Man Brewery Blueberry Berliner Weisse made from a yogurt starter

Yogurt Souring refers to the method of souring wort using unpasteurized yogurt. Greek yogurt is often made with Lactobacillus acidophilus, a lactic acid producing bacteria that is also associated with some health benefits . Using cultures of L. acidophilus from yogurt reportedly can make a 3.0-3.5 pH sour wort in 24 hours, without producing vomit/fecal flavors and aromas. To sour 5 gallons of wort with yogurt, make a 1 liter batch of unhopped starter wort the day before brew day. Add 2-4 teaspoons of live yogurt to the starter wort. Maintain a 100-110°F (37.8-43.3°C) temperature for about 24 hours. On brew day, and after the 24 hour sour starter is finished, mash and sparge a low IBU wort as normal, boil for a few minutes, and then chill the wort down to 100-110°F (37.8-43.3°C). Pitch the yogurt starter into the wort, and hold the temperature as close to the 100-110°F (37.8-43.3°C) range as possible. Bubbling CO2 through the wort is advised if possible to prevent potential off flavors, but is not required. Within 24 hours, the wort should be down in the 3.x pH range. Boil the wort, adding any hops that the recipe calls for, yeast nutrient, etc., and then cool the wort down to Saccharomyces pitching temperatures. Bob's your uncle!

Brands of Yogurt

In general, non-fat Greek yogurt that is unpasteurized works best. Brands of yogurt that have been reported to be successful with this method:

• Fage Yogurt
• Greek Gods
• Nancy's Yogurt
• Seven Stars yogurt - Mike Karnowski reported pH of 3.3 after 20 hours @ 110 F. Zero drop in gravity. Clean, soft lactic tartness, with the usual Lacto sulfur aroma that boils off .

Culturing Lactobacillus From Grains

Derek Springer's grain starter

If the brewer wants to use the LAB found naturally on the husks of grains, and doesn't want to risk pitching grains into the entire batch of wort, a starter culture can be made. The benefit of this is that if the culture contains any vomit, fecal, or putrid aromas, it can be thrown away and tried again. If the starter needs to be dumped, try again with a different malt source as microbial populations can vary greatly between maltsters, harvest years, and malt type . The following is Derek Springer's grain starter process :

1. In a 2L flask make a standard starter wort (1.040 OG).
2. Add 1/2 tsp 88% lactic acid (should get pH down < 4.5).
3. Add 2 cups uncrushed malt (using acidulated malt is not required).
4. Top off with carbonated water.
5. Cap with an airlock.
6. Keep as warm as you can for 2-3 days, ~110°F is best.
7. After 2-3 days, strain the grains out using a colander. Pitch the entire starter into the wort using one of the methods described on the Sour Worting page.

See also Microbial Populations on Barley.

Culturing from Kefir

Commercial kefir will have the microbial populations listed on the bottle. Many include Lactobacillus spp. The above process should also work well for home fermented kefir. Pietro Caira from MTF offers this guidance on culturing from commercial kefir products (President's Choice and Liberté brands specifically tested):

1. Let the kefir warm to room temperature.
2. Shake the kefir up in the bottle, and add to an unhopped 1 liter starter of ~1.040 SG DME wort (for a 5 gallon batch of beer).
3. Incubate at a temperature of ~100°F for 24 hours (room temperature may work too).
4. This results in a starter pH of about 3.2.
5. Add the entire starter to wort using one of the methods described on the Sour Worting page.

• See this MTF thread for more discussion/experiences on souring beer with kefir.

Culturing from Sauerkraut

Pellicle from Alex Loijos's sauerkraut culturing experiment.

Culturing LAB from sauerkraut can be done in much the same way as kefir. This study shows that culturing Lactobacillus from sauerkraut is most likely best done when the sauerkraut is at least 7-14 days old, however after 60 days more acid resistant Lactobacillus cells can be cultured. The following instructions can be used to culture LAB from sauerkraut (and probably from other fermented vegetables) for a 5 gallon batch:

1. Use 100 mL of at least 14 day old brine, but preferably 60 day old brine, and allow it to warm to room temperature if cold.
2. Add the brine to a 1 liter starter of ~1.040 DME wort (alternatively use Samuel Aeschlimann's Lactobacillus starter recipe).
3. Incubate with an airlock at a temperature around ~90°F.
4. Wait until the starter clears. This may take several days. When it clears, the starter is done. It may show signs of yeast fermentation.
5. After fermentation finishes, add the entire starter to the wort. Reference the Sour Worting page for further brewing procedures.

Alex Loijos described an interesting process on MTF of culturing successive microbes from a starting batch of sauerkraut. After preparing his sauerkraut, each day he took a sample of the developing brine and pitched it into the same batch of wort. This most likely had the effect of pitching Leuconostoc and Weissella species during days 1-3, and then Lactobacillus species starting on day 7.

The results of this experiment were interesting: "I just tried it cold. It's definitely drinkable!! It tastes like sourdough bread with the tart/salty/bready malt combination. I didn't perceive the viscosity as much and I think it's in part because it's flat that it feels 'thick.' I'm pretty pleased with the surprises along the way during this experiment. Chiefly that there were wild yeast that were capable of 71% attenuation, which I didn't expect! I was just using the kraut brine for souring, and expected I would have to pitch a culture after. Is there anything else like this that provides a pretty much guaranteed full spectrum of wild microbes (yeast and LAB)? Not yogurt, not grain, not coolships in the open air..." ~ Alex Loijos.

Culturing from Probiotics

Some commercial probiotics have been successfully used to produce Lactobacillus cultures (many brands have also failed at providing usable bacteria according to some homebrewers ). Probiotics that are classified as "dietary suppliments", as opposed to "drugs", may not be as free of contaminates as pure cultures from brewing industry yeast labs . The following probiotics are examples of brands, methods, and results that MTF members have had . Dried forms of Lactobacillus should be stored refrigerated because viability has been seen to decrease as much as 80x when stored at room temperatures .

See this Sui Generis Blog article on which Probiotics to avoid based on the genera of microbes they contain. Probiotics should have their contents listed plainly on their packaging. Avoid probiotics for animals as they tend to contain organisms that produce off-flavors such as Enterococcus, Clostridium, or Bacillus .

MTF Member	Source	Process	Results
Matt Firetto	Swanson Plantarum Probiotic Pills	Starter: 4 capsules Swanson Planatarum probiotic in 1 liter of 1.040 wort fermented in high 70°'s F in garage. after 36hr PH ~3.6 (using cheap wine PH strips) Tasted clean and noticebly sour with fairly strong yogurt like aroma. (not how I would want my beer to smell) Starter chilled over night and decanted most liquid before pitching Single infusion mash all grains at 153°F for 1hr 4.5 gallons strike water 3 gallons sparge water After mashing and sparging, wort heated to 190°F for 10 minutes and cooled to 95°F for souring used 12% acid malt in my mash to help drop the PH before adding the Lacto. Wort PH 4.5 using colorphast strips Wort gravity 1.040 pre boil/pre lacto Pitched decanted lacto starter Flushed Kettle with CO2, covered in plastic wrap and lid Wort PH ~3.7 gravity 1.038 pre boil/after 24 hrs (using cheap wine PH strips) No off aromas, nice fresh grain aroma. Tastes very clean, sweet, not as acidic as starter. 60 minute boil - 1 oz tettnang at 10 minutes .5oz tangerine peel and nutrient at 5 mins. Post boil gravity 1.040 Pitched US05 at 70°F Fermented for 10 days and kegged at final gravity 1.013	Tasted after 10 days in keg. Pours with bright white head, which mostly recedes but leaves good lacing. Simple aroma of grain and lactic sour aroma. No off or funky aromas. Taste is very bright with a sharp and simple sourness. No bitterness or hop flavors, but I think the tangerine peel helped to add more complexity to the sour flavors. Light grain character with just a little bit of sweetness. I also drank this side by side with an Ithaca Cruiser Berliner Weiss. Overall the beers were very similar. The Ithaca beer had a stronger grain aroma and a little less lactic sourdough aroma. Both beers seemed to have about the same perceived level of acidity. The acidity in my beer was just a little more bright than the Ithaca beer, but overall the two were very similar.
David Frank	Goodbelly Probiotic Drink	Warmed up 2 Goodbelly probiotic drinks to room temperature and then pitched it into unboiled wort(in a purged keg). Sour worted at 95°F.	Starting pH was around 4.7 (pre-acidified the mash). ph at 3.73 after 15 hours pH at 3.68 after 24 hours pH at 3.65 after 36 hours pH at 3.5 after 48 hours - massive co2(and possibly ethanol) production...when I purged the keg, the beer exploded out. The keg was under around 30psi. Very messy to get it out of the keg and into the kettle. Beer was then boiled for 20min, chilled and fermented with kolsch yeast.
Brett Smith	Goodbelly Flavored Drinks Probiotic Drink	700ml starter of 1.040 wort. Chill to 95°F. Fill to 1000 with Goodbelly drink. I like the mango as it doesn't seem to leave much aroma at all. Let this starter go for 24 hours. You'll see the massive growth. Brew beer however you choose. Cool to 100°F. Pitch Goodbelly starter. Let temperature free fall. Check pH in 24 hours, should be 3.4-3.6. I like to let my culture go 36 hours and I'm almost guaranteed 3.4. Then pitch yeast to ferment.	Described this above.
Ed Coffey	Swansons L. plantarum Probiotic Pills	Cracked open 3 pills and added to 750ml of DME starter wort, kept at 90°F for 36 hours then pitched into 100°F wort.	I've done this twice now, reached a PH of ~3.30 in 48 hours at 95-100°F.
Abel	Goodbelly Probiotic Drink	Let warm up to temp and pitch straight in.	Ph before 5.4, ph at the end was 3.2. Temp held at 95°F for 3.5 days then pitch Sacch and lowered to regular ferment temp.
Viktor Nyman	ProViva Superfrukt Probiotic Drink	Made a starter of 200 ml juice and 800 ml OG 1040 wort. Fermented at 35°C for a few days, cooled to refrigerator temperature and decanted into a sanitized container. A few days before the brew day, I made a new starter from the decanted bacteria and 500 ml of OG 1040 wort. Fermented at 35°C. Pitched the whole starter into a 15 litre batch.	The starter had a starting pH of 4.5 and was under 3 pH in 24 hours. This was when fermenting at 35°C. The beer itself started at 4.8 pH and I boiled it when it reached 3.2-3.3 somewhere 21 hours later. Result is clean and lactic without any sign of spoilage bacteria related off flavours (throw up, cheese, butyric acid etc.).
Drew Wham	GoodBelly Products (L. plantarum)	Their products contain 20 billion cells of the 229v L. planetarium strain per serving. In a 5 gal batch a single serving will reduce the pH to 3.2 in 48-72 hours held at 95°F.	Good results in over 12 batches.
Dan Graston	Swanson Probiotics	1 capsule in 1 quart of canned starter wort (1.039, 4.44pH, not DME) at 90°F.	Starter pH barely dropped for first 24 hours because the Lacto powder just sank to the bottom and never went into suspension, which was unexpected. After rousing, the pH dropped to 3.23 over the next 36 hours. No drop in gravity. Test starter, so no beer was produced.
Allen Stone	LactoGG	2 capsules were used in 1 liter of 1.030 wort, and held in high 90°F's for 72 hours before stepping up to 5 liters and pitched after another 7 days. The powder from the capsules fell to the bottom of the starter initially and needed rousing before it started fermenting.	I only had test strips, which indicated a ph in the high 3s. I tasted the wort at this point and it had produced some co2, but not much, and a slight tartness. I added Custersianus to ferment out and there has sat for many months. I sampled it recently and it is not great. Slightly tart, but not enough to stand on its own. I would like to do this again with more control, and build a small starter that is pitched into a larger volume of wort, then held at a higher temp. I suspect that because of the makeup of Lacto GG and its ability to survive internal body temp, it may need to work In the low 100s to really go to work. I would say it is a viable option, but not enough info is known at this time to give any suggestions.
Stuart Grant	Ethical Nutrients - IBS Support (Australia)	Added 120 billion cells. Pitched at 29°C/84°F, and I'm letting it fall to room temp. 20 hours since pitching got to 3.87 pH. Temp has dropped to 20°C/68°F. No change in SG (1.045). After 25 hours, temp down to 19°C and pH down to 3.67. After 35 hours, temp 18°C, pH 3.53, SG 1.045 (unchanged). Lactic flavour is very clean; slightly appley. It barely tastes tart with all that sugar. After 44 hours, temp 18°C, pH 3.43, SG 1.045 (unchanged). I split the wort in half. First half I boiled for 20 mins with some hops then pitched US-05; second half I did not boil, but added dry hops and Lochristi Brett slurry.	The no-boil version which had Lochristi Brett added is down to 1.016 and pH 3.32, while the boiled version pitched with US-05 is down to 1.008 and pH 3.23 (weird that it's lower). Brett version is quite funky with some acetic acid. Clean version is super clean, and ready for bottling soon. Lovely clean sourness. The dry hops come across as lemon zesty. Superbly refreshing! See Stuart's blog post.

Using Sourdough Starter

• Brian Hall's experience using a sourdough starter.

See Also

Additional Articles on MTF Wiki

• Sour Worting
• Commercial Sour Beer Dregs Inoculation
• Mixed Fermentation
• Wild Yeast Isolation
• Lactobacillus
• Pediococcus
• Grain

External Resources

• Brewing with Yogurt. The Not So Professional Beer Blog.
• Gosebier - Fermented with a Sauerkraut Culture? Ryan Brews Blog.
• Choosing the Right Probiotics for Souring Beer, by Bryan of Sui Generis Blog - tips on Probiotics to avoid based on their contents.
• Lactobacillus Plantarum Gose: Sourcing Lacto from Probiotics by Ed Coffey, Ale of the Riverwards blog. More details on Ed's positive experience with Swanson's Plantarum Probiotics.
• Sourdough Saison, The Beer Minimum blog. Good results making beer with a sourdough starter.