Anyone have any experience souring a beer with yogurt culture?

I read about this on a site or two, and it seems like a cheaper way to introduce the lactic bugs. For those of you in a part of the country with a significant Mexican population, you may be familiar with a "drink" stocked in the yogurt section called Bio-Salud. It's basically an oz of nonfat milk with active L. acidophilus, casei, bifidus, bulgaricus, and Streptococcus thermophilus. They are about 88 cents for 7 of them, and the bugs usually settle to the bottom. I think it'd be easy enough to make a starter out of them. I would assume the milk wouldn't cause a problem because of the eventual alcohol and acid content, and you could pour about 90% if not more of it off the bugs at the bottom. Another thing to think about is that they contain a small amount of sorbate, but I think it would be so small as to not affect a 5g batch. Any other reasons why this shouldn't work?

If its an ok idea, I think I'll attempt an Oud Bruin with it. I saw on another site someone had soured their mash with yogurt but only let it go 2 days before pitching yeast, and then the lactic character was only very very faint. I was thinking maybe pitching the bugs, waiting a week or two, then pitching the yeast and proceeding as normal. Can't do it the other way since high alcohol will kill off some of those bugs. Opinions?

EDIT: just found out L. delbrueckii ssp bulgaricus has a pH requirement, so I may have to let yeast go to work for a week or so before pitching bacteria. The other bugs like L. acidophilus have a pretty wide pH tolerance.

Well since I haven't gotten any definitive "no's" I think I'll go ahead and give this a try. Either it works and I have an oud bruin, or it doesn't, and I have a decent session ale (shooting for 4.1%).

Am I correct in my thinking that when making sour beers, you need a separate set of equipment unless the equipment is glass, which can be reused? Or will I need a separate set regardless. If glass is ok but better bottles are not, can someone explain the actual science behind that? Both are porous, and AFAIK all the lactic bugs I plan on introducing are non-motile non spore forming species. Therefore, theoretically, cleaning with a bleach solution and letting it sit for a few weeks before a "normal" batch would be alright. I don't mind getting additional stuff, I'd just rather not if I didn't have to.

sorry cant help ya here man...

I've done it twice for a sour mash. It worked pretty well.

I've done it twice for a sour mash. It worked pretty well.

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Awesome. I'll definitely be giving this a go then in the next couple of weeks. Anyone have any clue about the equipment question?

Re: the equipment, the adage of a seperate set is - to my knowledge - primarily dealing with bugs like Brettanomyces or Pediococcus. I didn't see anything in your list that jumps out as dangerous of infecting your gear. If it does, an OxyClean soak would potentially fix it anyways. I *think* you should be fine, but I'm not 100% certain in my answer.

Just snuck a taste of this. It's great! I let it sour with the lacto for 3 days then pitched the yeast. It ended up being just the right amount of sour. The nasty lacto blobs have mostly settled to the bottom as well.

In 2 weeks, I'll be taking this to a glass secondary I got off CL and introducing brett. I was originally going to split the batch, but after have my first few Orvals, I'll throw brett in the whole 5g.

Phissionkorps - How did this ultimately turn out? I'm very curious to hear what came of this little experiment. I recently came across a similar yogurt culture (specifically a bacteria culture for making yogurt) in my grocery store and was thinking about doing the same thing. Did it end up tasting very yogurt-y? or more like a balanced sour beer?


Just curious. Any response appreciated.