Bacteria Flavor Profiles

[5mooth0perator]

I've been playing around with probiotics to make sour ales. I've tried a couple, a ten strain stomach probiotic and a five strain ear nose and throat probiotic. I've been making starters and I tasted the starters without the yeast. The stomach probiotic tasted sour unsurprisingly it consisted of many Lacto strains, though it also had wine like qualities and also some yogurt or kefir flavors. The ear nose and throat probiotic was much milder but developed a sourness, but also had more residual sweetness, I'm guessing the fewer strains would naturally not ferment as many sugars, and overall took a lot longer to sour.

It makes me wonder though what are the flavor profiles of bactetia? I know one of the preferred species is pediococcus. However, most literature seems to indicate that Lacto strains contribute lactic acid only, but that doesn't seem quite right.

 

[microbusbrewery]

I'd say the primary contribution is lactic acid from the various lactic acid bacteria (LAB), but they also produce other compounds. Pedicoccus will create a bunch of diacetyl along with lactic acid, which is why it has to be partnered with brettanomyces. Brett converts diacetyl to other more desirable compounds. So I would say that's more of a flavor and aroma contribution from brett than pedio. With lactobacillus you have homofermentative strains and heterofermemtative strains, and some that are capable of both under certain conditions. Homo primarily produces lactic acid whereas hetero produces lactic acid and ethanol, and sometimes acetic acid if the conditions are right. I'm not sure what all the "other" compounds are that are produced by the various lactobacillus strains, but my understanding is they're minor in comparison to the lactic acid production. I don't think that totally answers your question, but hopefully that helps a little.

 

[5mooth0perator]

I'd say the primary contribution is lactic acid from the various lactic acid bacteria (LAB), but they also produce other compounds. Pedicoccus will create a bunch of diacetyl along with lactic acid, which is why it has to be partnered with brettanomyces. Brett converts diacetyl to other more desirable compounds. So I would say that's more of a flavor and aroma contribution from brett than pedio. With lactobacillus you have homofermentative strains and heterofermemtative strains, and some that are capable of both under certain conditions. Homo primarily produces lactic acid whereas hetero produces lactic acid and ethanol, and sometimes acetic acid if the conditions are right. I'm not sure what all the "other" compounds are that are produced by the various lactobacillus strains, but my understanding is they're minor in comparison to the lactic acid production. I don't think that totally answers your question, but hopefully that helps a little.

I think homofermentive and heterofermentive explains most of the observed differences.