Maybe this is a stupid post but I figured I'd ask anyways. What would happen if you left a sour mash going for an extended period of time? Is there a point in which the lacto can no longer sustain itself and dies off? Will the ph get too low and stop, and would this cease the process of souring? I made a couple Berliners and held them under a heat lamp for a week to give them a big amount of sour, now I'm considering waiting even longer to see what happens.
Yes, at a certain point the bacteria will lower the ph to the point they can no longer remain active. I'm not sure if wort will reach that ph level before fermentable (for lacto) food sources have been exhausted. At some point, one way or another, lacto fermentation will stop at a fairly low ph. I have pushed a sour mash down into the mid 3's.
I did a sour wort, and got it to 3.3 before I stopped it as well. Eventually, the environment will become too hostile for most anything. Probably including your tastebuds and tooth enamel.
Mine wasn't. It's sour, more sour than.. 70% of commercial stuff I'd have to say. It was on par with the 1st run of Westbrook Gose in the sour dept. Took me 6 days at 70* with grain, but added 3mL of lactic acid at the start of souring to get the initial drop quickly to keep it from getting funky.
In my case I only soured half of the mash so the overall beer ended up in the upper 3-lower 4 range. It is slightly more sour than berliner weisse but not quite an aged sour. I soured at 105F for four days to drop down to the mid-3 range.
The other thing to watch for is dropping the pH so low that the brewer’s yeast to follow aren’t happy. You can go below 3.5, but that’s where you need to be more conscious of pitching extra yeast, adding extra yeast nutrient to the boil, selecting a strain that deals with low pH well (like Wyeast 3711 French Saison).
Hmm maybe this is why my FG's were high on the last two batches. At first I attributed it to high mash temp, but after I corrected it I still finished at 1.014, this is with an OG of 1.040 I sour mashed for 5 days both times, slowly went from 120F to 80F over that time period. Just pitched US-05 straight in. I'll grab some ph strips this weekend and take a measurement. FWIW even though they finished high they still tasted awesome.
Just read about PH and gravity yesterday, http://drunkalchemist.blogspot.com/2014/07/effect-of-ph-on-flavor-profile.html
Is a sour mash really worth the extra time and stench? Seems like a big pitch of lacto would be so much easier.
Stench? Never had one from it, except the batch that spilled due to a faulty box haha. Sour mash allows me to boil off the lacto as well which keeps my cold equipment lacto free. Also IIRC there was an experiment done with lacto, and the best results of sourness were achieved by first allowing the lacto to do it's thing, and then pitching a clean yeast once the lacto is done. Basically I listen to FATC1TY and read that long thread, though he collects the wort and sours that instead of the mash. I like doing the mash, just easier on my schedule. It only takes two hours or so and is easy as hell, and if I wasn't sour mashing I would still let the lacto go first so it wouldn't save any time for me.
I've never done a sour mash, but haven't heard great things from those who have done them. Might give it a try on my next Berliner.
If you want to dry the beer out more, I'd look at mash temps in the 146 - 150 range. No point in mashing high for dextrins if your killing off the lacto in the boil. Second option is that you carry over some lacto from the sour mash to the fermenter and mash high. This will allow those complex sugars to be digested as fermentation & conditioning ensues by the active lacto in the fermenter. I've had good success with this method; souring mash + transferring some lacto to the fermenter with saccharomyces. If lacto hits the fermenter, I bet your 1.014 FG at least drops a few units.
Yeah that was the range I mashed. First one I was like 165F by accident, second one I hit 150F. This time I hit my goal of 145. I'd hazard a guess that the second finished high because I just threw in a packet of 05, didn't bother rehydrating or anything. The first could have been the mash or the yeast, they didn't have 05 (WTF??) so I used WB-06 on the first batch. I wonder if it will taste better dryer though, damned if the first two weren't freakin delicious.
