Culturing Lactobacillus from Yogurt & Grains with a Crock Pot/Slow Cooker

[ajfranke]

"Lacto Two Ways"

One of my next brews will be a gose. This is my first foray into sour brewing, so in full disclaimer: I have no idea what I'm doing :fro: . Instead of purchasing a lactobacillus culture from Wyeast or White Labs, I'm going to try culturing some from another source. The two sources that I'll be trying to culture from are commercially-made yogurt, and unmashed acidulated malt.

In biology labs, a common method for keeping cultures at optimal temperature is to place them in a water bath held at optimal growth temperature. This equipment is what I will try to replicate with a slow cooker and temperature controller.

Equipment:

• One jar, Chobani brand yogurt.
• Acidulated Malt (I think it's from Briess?)
• Two washed & sanitized jelly jars.
• Slow cooker or Crock-Pot with deep interior. Mine is Hamilton Beach brand.
• Temperature controller and Solid-State Relay (SSR).
• Spoon.
• Dry Malt Extract.
• Plastic Wrap & Rubberbands.
• Sanitizer (I use StarSan).

First, I configured the temperature controller to cycle the power on the slow cooker. I'm sure there are tutorials on how to do this on these forums. The temperature probe is threaded in through a hole in the slow cooker lid. My slow cooker has a particular "feature" where one can use different-sized vessels for the bowl, but requires you to press a button to select bowl size each time the unit is powered on. The "fix" for this was to place a heavy jar in front of the unit (the chocolate sauce, in the picture) so that the appropriate button is held down. After filling the bowl with warm water and powering-on the unit, the slow cooker took about 20 minutes to reach an optimal temperature of 120F. My cheap temperature controller appeared to hold it within 1 or 2 degrees, which is good enough for our purposes.

Next, I filled each of the jelly jars with 250mL of water and 25g DME. After covering them with plastic wrap, they spent 15 minutes boiling in the microwave. The starters were cooled in a cold water bath, then allowed to rest in the 120F slow-cooker bath for a few minutes.

Now to begin culturing! After carefully opening the yogurt cup, I used a sanitized spoon to scrape off the whey-rich liquid at the top. This was then stirred into one of the starters, and the starter covered and the plastic wrap secured with a rubber band. After re-washing and re-sanitizing the spoon, I then took a scant spoonful of the acidulated malt and stirred it into the other starter. Again, covered and secured. These were then left to sit in the water bath overnight.

The results so far:

The first picture is the Yogurt culture: there's a small layer of tan stuff at the bottom (bacteria?) but no pellicle. The second image is the malt culture: there's a slightly-thicker layer of tan stuff at the bottom, and some small chunks of grain, but no pellicle. Unfortunately, I didn't have an opportunity to taste either this morning.

I'm going to keep the jars in the bath for a while longer, to see if more growth occurs or if a pellicle forms.

Helpful tips, comments, or questions are appreciated!

 

[Nanobru]

I strongly recommend sticking with commercially available yeast cultures. The time it takes for a lambic (6 months to a year) will be wasted, and you will be extremely disappointed. There are many different strains of lacto and brett, and the chances of making vinegar are too great. Increase your chances of success by using tried and true ingredients and techniques.

 

[ReverseApacheMaster]

I would assume you have some lacto in there but there's probably a lot of other stuff, especially in the grain-based culture. I think you will be fine using those cultures for gose but it might be less clean than using a culture from wyeast or white labs.

 

[spearko520]

lots of people have done lacto infections with good results. There are a number of different ways to control them - you can use a sour mash and boil off the lacto when they get the ph lower, or do something like you are doing. i usually just throw a little bit of sourmalz in the primary (i only chill to like 100 degrees) and i keep it at 100 -110 with a heater for a couple days, until i get acitivity- i have never noticed a pellicle forming from lacto, usually i don't see pellicles on brett stuff for a few months. after i get some activity, i aerate and pitch a healthy starter, and this seems to take over the wort. a gose doesn't take as long as a lambic, anyway. i've been using wild fermentation techniques for a pretty long time, and i am definitely no expert, but i can tell you, i've never been disappointed or felt like i wasted my time. Sometimes i wished i had been more patient, and sometimes i wished i still had certain batches to blend, but i say go for it if you want to foray into an area that's a little less constraining. It is very unlikely that you will produce an exact clone of any commercially available wild beer, no matter what yeast strains, bacterial cultures, or techniques you use- but that doesn't mean that you can't make an awesome beer. you can also get some differing strains of lacto from acidophilus caplets at the health food store or pharmacy.

 

[Native302]

I strongly recommend sticking with commercially available yeast cultures. The time it takes for a lambic (6 months to a year) will be wasted, and you will be extremely disappointed. There are many different strains of lacto and brett, and the chances of making vinegar are too great. Increase your chances of success by using tried and true ingredients and techniques.

this makes me sad because I like what you are attempting to do and the fact that you are experimenting and looking beyond the realms of "convience" so you can do something from scratch by hand. Bravo and please keep us (me) posted on your results.

 

[Tinga]

I don't believe you need to use aciduated malt to make it sour. any grain will do.

I have done a couple small batch sour mashes in a 2 gallon water cooler BIAB style. I do a simple infusion mash at 150 for an hour then add enough cold water to get the mash down to under 120. When the mash is under 120 I add a handful of whatever base malt I happened to use. normally 2 row. I put some saran wrap on top of the liquid and push out all the air bubbles. This helps to keep the other nasty bacteria out. Then I place my cooler in my incubator (rigid foam board insulation, water heater thermostat and a light bulb). I do this for two to three days depending on the level of sourness I want. I haven't failed yet and I haven't had any hint of the other potential nasties.

I made a sour brown and have been pitching sour beer dregs into it but I'm not sure how much it has taken off. I think my next plan is to do a sour mash gallon or half gallon, not boil and pitch brett onto it like a starter. then put that small batch into the bigger one.

 

[riored4v]

I've done a similar method with using the grains (just basic 2-row). I will use a honey/water mixture of around 1.035 OG and then add my grains. I'll keep that 100* for about 3 days until the lacto forms. Once that is done, i'll mash my beer as normal and then collect the wort, bring it to a boil, flame out and chill it down to 100* again. I'll toss it back in my cooler, add the lacto culture (sour starter) and then let it sit atleast 18hours will it sours the wort. You can taste it as it goes to get it to the level you prefer. Did a Berline Weiss this way and it was excellent. Doing a sour brown this way right now that I'll be adding some tart cherries to.


IMG_0515 by riored4v, on Flickr


IMG_0516 by riored4v, on Flickr

Wort-before:

IMG_0522 by riored4v, on Flickr

After:

IMG_0525 by riored4v, on Flickr



IMG_0609 by riored4v, on Flickr

 

[Tinga]

I've done a similar method with using the grains (just basic 2-row). I will use a honey/water mixture of around 1.035 OG and then add my grains. I'll keep that 100* for about 3 days until the lacto forms. Once that is done, i'll mash my beer as normal and then collect the wort, bring it to a boil, flame out and chill it down to 100* again. I'll toss it back in my cooler, add the lacto culture (sour starter) and then let it sit atleast 18hours will it sours the wort. You can taste it as it goes to get it to the level you prefer. Did a Berline Weiss this way and it was excellent. Doing a sour brown this way right now that I'll be adding some tart cherries to.

Holy wow those are some gnarly pics. Have you ever had problems with puke smells? I read that you need to minimize contact with oxygen because Clostridium is aerobic and will out perform lacto if there is oxygen. I mean I guess if you said it turned out well for you. I assume you wouldn't think a puke aroma is good. Maybe I don't need the saran wrap after all.

 

[troub]

I've done a similar method with using the grains (just basic 2-row). I will use a honey/water mixture of around 1.035 OG and then add my grains. I'll keep that 100* for about 3 days until the lacto forms. Once that is done, i'll mash my beer as normal and then collect the wort, bring it to a boil, flame out and chill it down to 100* again. I'll toss it back in my cooler, add the lacto culture (sour starter) and then let it sit atleast 18hours will it sours the wort. You can taste it as it goes to get it to the level you prefer.

And then what...the full 60 min boil with hops, etc., right?

 

[riored4v]

And then what...the full 60 min boil with hops, etc., right?

I did a 90 minute boil, but yea. You transfer back to the kettle, boil as normal.

Holy wow those are some gnarly pics. Have you ever had problems with puke smells? I read that you need to minimize contact with oxygen because Clostridium is aerobic and will out perform lacto if there is oxygen. I mean I guess if you said it turned out well for you. I assume you wouldn't think a puke aroma is good. Maybe I don't need the saran wrap after all

Naw, no puke smells on mine. Smelled VERY similar to a tart green apple. I kept loose tin foil on my flask.

The berliner weiss has also scored very well in every comp I've entered it in, so I'm definitely happy with this method for now.

 

[JacobS]

Reminder for me

 

[pohldogg]

I strongly recommend sticking with commercially available yeast cultures. The time it takes for a lambic (6 months to a year) will be wasted, and you will be extremely disappointed. There are many different strains of lacto and brett, and the chances of making vinegar are too great. Increase your chances of success by using tried and true ingredients and techniques.

I think that the WL/WY lacto can be a bit "sissyish" compared to some other LAB and that's why dregs and ECY are so appealing. Instead of culturing from yogurt, I've picked up some freeze dried cultures from Whole Foods. If they can sour milk in a couple of hours they ought to be able to put a sour into some wort. Plus, the yogurt starter packs should reduce the chance of infection compared to culturing up from a cup of yogurt.