What does brett, lacto, and pedio do to C-malts?

Doubt it. They usually have their own unique flavors but i'm a newbie using a brett L.

 

Depends on time, pitch rate, and what specific strains you're planning on using. Given moderate pitch rates and plenty of time, it's likely that most Brett strains could chew through pretty much any dextrins or "unfermentables" that have been left behind by standard saccharomyces fermentation.

 

Brett produces exo-enzymes that can break dextrins down into sugar, so they make the beer more fermentable with time, as @TomTown indicated. I suspect that the lacto and pedio strains have some capacity for this as well, but regardless, if Brett is freeing up sugar from dextrins, other bugs will try to use that sugar too. I haven't made tons of sours, but the ones I have lost residual sweetness and body and became more sour as they aged.

 

I brew lots of sours but have to admit I have rarely if ever used c-malts, I would assume quite a bit less sweetness than you would get with a sacch beer.

 

One thing you could play with if you want sweetness in sours is blending. I have enjoyed some commercial sours blended in the glass with homebrew porters and brown ales. If you wanted to do this with bottled beer you should cold crash as soon as the blended beer is carbonated (or the brett will remain active, eating any residual sugar and dextrin sand creating bottle bombs too. Or you could blend in a keg, lower temps, and force carb

 

Sweetness will more than likely disappear, but the flavor of the malt sans sweetness will carry through. Special B will give a raisin quality but not a sweet raisin quality.

I'm also going to disagree with @pweis909 and say that crash cooling a blended product will not stop the Brett. From brewing with solely Brett for well over a year now I can easily say that Brett will continue to work at 35*F, much slower, but it will produce enough CO2 to over carbonate, even in a keg.

 

Again, my experience is limited, but my old bruin retained some sweetness when I stored the bottles at about 32-35 F. I didn't mean to imply that it would shut the brett down completely (nothing is forever) but was thinking more about reaction rates slowing with temperature decreases. Find the taste you like, then slow things down as much as possible to preserve it. And then drink like there is no tomorrow . I should add, that for keggers, you could blend to find what you like, shut the bugs down chemically with sorbate or similar means, cold crash and force carbonate.