Carbohydrate Utilization by Lactic Acid Bacteria

[rzeccola]

Hi all. Question for you.

To the best of my understanding, in a lambic or sour fermentation, saccharomyces is still responsible for the bulk of sugar > EtOH conversion, but there are other more complex carb molecules that sacch. is not a specialist in that are usually then left to Bret, Pedio and Lactobacillus for more fermentation.

Does anybody know precisely what these other three bugs are chewing on?

Any insights would be helpful.

 

[PDX_T]

They all ferment sugars like glucose, fructose and sucrose. All pedio and some lacto strains only produce acid from those sources. they're called homofermentative - think yogurt. Some lacto strains can also metabolize starches and other glucans, and will produce alcohol as well as acid. those are called heterofermentative.

Wild yeasts will metabolize a variety of longer chain dextrins, and even some odd sugars like xylose and raffinose.

 

[biertourist]

Well I hoped to respond to this one but I don't really need to as PDX_T has completely covered it.

The homofermentative strains simply take one sugar in and produce one acid out.

Adam