Mixed culture fermentation Q

[CPR]

I'm working on developing a mixed culture for farmhouse/saison beers, something that more fully reflects a) the historical saison flavour profile (i.e. more acid, more funk), and b) tastes a little more like my favourite modern commercial farmhouse beers (i.e. mixed-fermented American and Belgian beers, like Fantome, Jester King, Oxbow, etc.), compared with just brewing a "saison" with a simple smack pack of 3711 or the Dupont stuff.

I've got a great blend right now, I think, made up of the following yeast and bacteria:

-Bastogne/WLP510 (thanks Brian)
-Yeast Bay Saison Blend
-wy Brett Lambicus
-wy Brett Brux
-Bellwoods Brettal Head keg dregs (itself a blend of Brett L and Brett B I believe)
-Jester King bottle dregs (a massive slurry thereof, including a blend of the main saison yeasts along with dregs from Phantome/orval/etc, plus "Texas wild yeasts and bacteria")

... I've been building the slurry for weeks, enjoying how the flavours have been shifting as certain organisms declare themselves kings and queens of the mix. One flavour I've been trying to suppress by hopping is a certain lactic acid bacteria "twang" we'll call it. Slightly vegetal, lemony, and just a bit bad. (Anyone who's messed up a Berliner knows this flavour). My latest starter brew was just two days ago and it's already down to 1.003 from 1.035. Smelling and tasting great except for that bit of twang.

My question is: Is there anything else I can do to limit the amount (or expression of) the lactobacillus in this culture? Higher IBUs helps for sure, but is there anything else I can do? I want the lacto in there, it's adding a beautiful acidity, but I guess what I want it less of it. Halp?

[jacinthebox]

This is well beyond my brewing level. Look forward to hearing what you come up with.

There's a lot going on in that slurry so I'm not sure how to control the lactobacillus. ..other than adjusting the pitch to have another bug take over...or like you said...more hops

[jeffsmith]

Is there a wort pH you can shoot for that will promote the growth of the other bugs but hinder the lacto?

[CPR]

Seems like lots of brewers pre-acidify wort when using lactobacillus, but mostly in the context of beer that the brewer intends to be quite sour (seems to help with the foam-killing problem lacto can have, too). In my case, I want the lacto present, but subtle. It's funny, my saison strains enjoy a high fermentation temperature (my current starter is at ~80ºF), but I think that if I increase the IBUs slightly, again, and ferment at a lower temp, the lacto shouldn't express itself quite as much. I don't think the culture will appreciate being thrown into a 68ºF wort after the tropical bath it's just been enjoying, but we'll see. So: lower the temp, up the IBUs? I'm thinking yeah.

[jeffsmith]

Worth a shot. Can you split the culture so you have a baseline if that doesn't work out?

[CPR]

Absolutely, yeah. I've got a carboy-sized starter on the go now, gonna try this next bit in maybe a 500 ml erlenmeyer. Cheers!

[jacinthebox]

Maybe make a sour mash...stop when u hit your desired sourness...boil to kill the lacto...then use ur other bugs to ferment? It's not really what your trying to do I know.

[MitchK]

So when people ferment with wild yeasts and bacteria, can that fermenter ever be used for "clean" fermentation with pure commercial yeast again or is it safe to say the threat of lacto will always be there forever (at least in plastic)?

[Celiacbrew]

CPR if you have a lacto strain in your mix and it grows faster than the rest of your mix won't you always end up back to the equilibrium it's at now? If you can't brew a beer you like with the mix you have maybe you could plate out as many of the bugs as you can to rebuild your mix and then put a more hop sensitive strain of lacto in instead of whatever you picked up from your bottle dregs. I heard a brewing network podcast (Sunday session I think) recently where a brewery adds as much bitterness as they can to combat their lacto strain. Maybe writing to them would get you some additional advice. I don't remember the episode but the episode was from the last couple of months.

[CPR]

So when people ferment with wild yeasts and bacteria, can that fermenter ever be used for "clean" fermentation with pure commercial yeast again or is it safe to say the threat of lacto will always be there forever (at least in plastic)?

The accepted opinion seems to be that heat & caustic will kill all yeast and bacteria on stainless, and on glass carboys. Plastic or wood is another story; brett and bacteria -vs- "clean" beers need dedicated equipment.

[CPR]

CPR if you have a lacto strain in your mix and it grows faster than the rest of your mix won't you always end up back to the equilibrium it's at now? If you can't brew a beer you like with the mix you have maybe you could plate out as many of the bugs as you can to rebuild your mix and then put a more hop sensitive strain of lacto in instead of whatever you picked up from your bottle dregs. I heard a brewing network podcast (Sunday session I think) recently where a brewery adds as much bitterness as they can to combat their lacto strain. Maybe writing to them would get you some additional advice. I don't remember the episode but the episode was from the last couple of months.

That's the thing, except that as I've adjusted my wort (with higher IBUs), the lacto HAS been reducing, i.e. I've gotten beers closer and closer to what I'm looking for. I read last night that lacto can become hop tolerant or be inhibited by hops even over a couple of generations, and that many strains can be "trained" to be tolerant or not over a few generations. Really aiming to avoid getting into the plating game; the best mixed cultures have too many strains to be plated efficiently, I'm told. We'll see what the next week brings and I'll report back. Thanks!

[CPR]

An update...

In this case, that aforementioned "lactic twang" as I was calling it, seems to have sorted itself out with more time in the primary. It was replaced with a burnt/ashtray phenolic, but after raising the temp once again on the fermenter, that flavour is also being scrubbed out too. Currently, about 11 days into this latest fermentation, my test beer/starter is sitting at 1.001 and tasting/smelling great. It's kind of an odd thing to say, but after speaking some more with Garrett from Jester King and reading from other brewers in this scene, beers brewed with cultures like this will generally sort themselves out given time. This is rustic/sour brewing, apparently. You have to be willing to trade the predictability of pure lab cultures for the relatively unpredictable je ne sais quoi of a more complex, subtle beer. That's not to say that anything goes; my blend was chosen pretty carefully, and there definitely are flavours that WON'T sort themselves out over time, especially acetic acid bacteria infections, but, if a flavour is not killing you, just wait (and, usually, blend), say the experts.

[CorneliusAlphonse]

Great! To me the burnt thing is the one flavour I've had in lambic and really disliked (I think maybe aa 3fountainen oude gueuze) but I agree. Time tends to sort these things out.

[MitchK]

I just like to say (kinda off topic) that I'm super glad to see people doing brett and lacto beers on here because that's something I'm really interested in doing eventually once I feel more comfortable with my setup. Maybe it's because I keep associating them mentally with sourdough.