Propionic acid

[BDF]

Hey Jimbo, what other variables have you controlled for?

A big one I've not heard talked about is temperature, What temp was the mash when you left it over night? What temp was it when you pitched? What temp was it fermenting at?
New grain supplier sounds suspicious as well, was your uber run done using that supplier's grain? If not does the label on the packaging have any other weird ingredients?
Might it be worth it to pasteurize all the grain and use those high temp enzymes you used in the flour thread to make up for the denatured ones in your malts?

[Jimbo]

Hey Jimbo, what other variables have you controlled for?

A big one I've not heard talked about is temperature, What temp was the mash when you left it over night? What temp was it when you pitched? What temp was it fermenting at? Mashed at 145 for 90 minutes wrapped in a quilt, then unwrapped and pointed a fan at the barrel overnight. It was 95 by morning, then dropped a wort chiller in (sterilized) and brought it to 78 where I pitched yeast.
New grain supplier sounds suspicious as well, was your uber run done using that supplier's grain? If not does the label on the packaging have any other weird ingredients?different corn but actually cleaner than last, and also washed it anyway. nothing listed on tag on either bag
Might it be worth it to pasteurize all the grain and use those high temp enzymes you used in the flour thread to make up for the denatured ones in your malts? Its the same malts I used in the successful run. Tonight I am gonna seperate the sweet wash from the mash and pasteurize it, cool it quick, aerate the hell out of it and repitch fresh yeast. Act of desperation to save this big batch from the compost.

First go get a big hammer and beat the crap out of something till you are sweating. Then sit down have a drink and ponder your situation.

Thats some damn fine advice.

[S-Cackalacky]

With that fan blowing on it overnight - maybe an airborne contaminant? Just kinda grasping at straws for a reason it failed.

Will be interesting to see what effect, if any, the pasteurization will have on it.

Good luck,
S-C

[S-Cackalacky]

Corene, about that hammer thing - are you speaking from experience?

S-C

[BDF]

Its the same malts I used in the successful run. Tonight I am gonna seperate the sweet wash from the mash and pasteurize it, cool it quick, aerate the hell out of it and repitch fresh yeast. Act of desperation to save this big batch from the compost.

How do you aerate it? A compressor and bubbler? Ultrasonic vibrations?

If you're pumping air into the mash might there have been different stuff in the air on the day that you were successful and the day you weren't? Like if it was rainy one day might there have been mold spore floating around?

[Jimbo]

Thats an interesting thought. It was -8F outside last night (65 in brewroom) so not too many mold spores out and about these days but air quality could be a factor. I use a large paint stir paddle made for stirring 5g buckets of paint. New, sterilized before every use, and whip the shit out of the mash. This whole process Im describing has worked for a long time and many many batches. This is whats making this so maddening now.

S-C, the barrel lid is on, but I suppose since its not clamped and airlocked, some molecules could find their way past the loose seal? Cant really airlock a hot barrel, when it cools it will collapse in on itself.

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[BDF]

This whole process Im describing has worked for a long time and many many batches. This is whats making this so maddening now.

Welp, something is different...

How do you store your grain (both new and old)? Might it have gotten damp and contaminated with something that could survive the boil? Could something have happened to the water in your airlock? Inspect your equipment for both mashing and storing and see if there's anything you can find out.

Good luck! And btw what ever happened to that all-flour mash(wash?) that you made?

[Jimbo]

Bags of grain are fresh and same as used week prior, except the corn we discussed. Thanks for you thoughts. Banging my head on this one, welcome any thoughts, even longshots .

On round 3 of flour wash. Will be doing a spirit run this weekend. Great stuff so far. Very tasty. Ill post up after the spirit run, and again a few months down the road. One of my favorites to date is a 100% wheat malt I do (the single malt recipe in my sig, done with wheat malt). Incredibly tasty stuff after a year in a barrel. Will be curious if this compares at all, that would be pretty amazing at $14 for 50 lbs of flour, vs $48 for 50 lbs of wheat malt. This wheat flour run will be cut as a whiskey and aged on oak for many months. If I had a reflux still I think it would make a great vodka too. Someday.

[corene1]

Corene, about that hammer thing - are you speaking from experience?

S-C

Why Yes! Yes I am. It has a very calming effect and lets me think!

[corene1]

OK Here is a long shot. I have been re reading what is going on. You are using 3 pounds per gallon for your mash so basically 80 pounds of grain and 27 gallons of water. Was there a difference in the crack on the corn between the good run and the bad run? What size and dimensions are the fermenter. Is it tall and slender or short and fat? Here is a thought. If the failed wash had a finer crack on it and you ferment on the grain. Is it possible that the amount of grain turb on top of the yeast bed could isolate the yeast enough to prevent fermentation? I had some corn once that was a very fine crack and had a lot of corn flour in it. It did not work as well as my older courser steam rolled corn. It was like it formed a plaster like layer over the yeast bed and sealed it off. I went back to the old corn and it was good again.

[Jimbo]

This new corn crack is smaller. But any flour that was in there I thnk I washed away when I washed the corn, After aerating I pour the yeast slurry on top and leave it. No stirring. In beer this is what they recommend. Not positive but its to allows the yeast to ramp up instead of just exploding your wash/wort all over the place (altho it still does sometimes). I would think it would be somewhat on top of the grain bed then? Also, After no activity in 3 days I whipped it up some more just in case I didnt aerate it enough. Still nothing. Today im gonna sqeeze out 80 lbs of grain and bring the clean wash up to 180 for a few minutes to pasteurize it, then cool and reaerate and pitch. Desperation. What a royal pain in the ass, I should be doing 2 stripper runs this weekend, not dicking with my damn ferment like this.

[corene1]

This new corn crack is smaller. But any flour that was in there I thnk I washed away when I washed the corn, After aerating I pour the yeast slurry on top and leave it. No stirring. In beer this is what they recommend. Not positive but its to allows the yeast to ramp up instead of just exploding your wash/wort all over the place (altho it still does sometimes). I would think it would be somewhat on top of the grain bed then? Also, After no activity in 3 days I whipped it up some more just in case I didnt aerate it enough. Still nothing. Today im gonna sqeeze out 80 lbs of grain and bring the clean wash up to 180 for a few minutes to pasteurize it, then cool and reaerate and pitch. Desperation. What a royal pain in the ass, I should be doing 2 stripper runs this weekend, not dicking with my damn ferment like this.

I was just thinking that if the yeast bed got smothered it would leave the top of the mash raw with no alcohol and spoiling could start. On the other hand it is a sterile environment so that theoretically should not happen. I sure hope you get this ironed out. This kind of stuff is what makes us old and gray, thank goodness I can use Loreal cause I'm worth it! Or maybe I should re quote that to read , because " I need it":D

[Jimbo]

This kind of stuff is what makes us old and gray, thank goodness I can use Loreal cause I'm worth it!

Na, this is just a pain in the ass, my kids make me gray tho. This is actually my escape to keep me sane. Ill try to play the optimist, and say this is a learning experience (and if you believe that bullshit Ive got a bridge for sale too).

Im running the last wheat flour wash now, and spirit run to follow, so life is good.

Ive dumped so much acidic spent grain and bad low pH wash in the garden that Im gonna have to pick up a bag of damn lime to sweeten the soil back up in teh spring!

[humbledore]

I reread this whole thread and just want to throw it out there...did anyone measure pH? I have been having weird pH problems. One of them started when I added a bunch of spent grains into another ferment. I know I'm not educating any of you, but once fermentation does start if the pH was low to begin with it drops even lower. And low pH will for sure stall fermentation.

[Alphacheese]

I reread this whole thread and just want to throw it out there...did anyone measure pH? I have been having weird pH problems. One of them started when I added a bunch of spent grains into another ferment. I know I'm not educating any of you, but once fermentation does start if the pH was low to begin with it drops even lower. And low pH will for sure stall fermentation.

According to the primary literature the lower the pH, propionic acid begins to inhibit fermentation. At pH 6.0 it doesn't seem to do have any inhibitory activity to Saccharomyces cerevisiae. As the pH drops to to 5.0 and especially 4.0 fermentation slows down and at higher concentrations of propionic acid comes to a complete stop.

As others have pointed out it's completely miscible in water so washing it off the corn should remove almost all of it. Ultimately it doesn't seem that it would have any effect of the yeast activity as a preservative in the corn, even if not washed off.

I've attached the article if anyone cares to take a look. Here is NCBI's link: http://www.ncbi.nlm.nih.gov/pubmed/21701869" onclick="window.open(this.href);return false;" rel="nofollow

[Jimbo]

Its a good thought Hum, I checked pH, and it was actually a touch high. Bourbon mashes with no backset are typically high in pH (corn doesnt help bring the pH down like malt, All malt mashes are generally in the prime range pretty much by itself (why pH adjustment is rarely necessary when making beer).

I use gypsum and lactic acid to pH adjust in bourbon mashes with no backset. I went light this time because I added some spent grains from last weeks batch, sourmash style. But it was still a touch high. I added a little more lactic acid. But alas, no luck, still dead as hell.

[BDF]

Did you try adding yeast nutrients, like you might in a pure sugar wash? Maybe the new corn brand and or spent grains are devoid of something the yeasts need?

[Halfbaked]

Not sure if this will help http://www.ag.ndsu.edu/news/newsrelease ... -wet-corn/" onclick="window.open(this.href);return false;" rel="nofollow but there are 2 phone numbers at the bottom that might prove better to help solve getting rid of the yeast killer.

[S-Cackalacky]

Jimbo, what happened with the pasteurized wort experiment?

S-C

[Jimbo]

I never got around to it. Stuff is starting to smell, so I gotta just pull my boots on and make a few trips to the garden to dump this shit. Frustrating couple days. Last run of wheat flour yesterday scorched too. No idea why. Ran same way as last one. Will post up over in that thread some thoughts.

Sometimes shit just seems to go wrong in spades. On the plus side I been hanging shelves and organizing my workshop and brewroom. Its lookin nice.

[S-Cackalacky]

What have you done to piss off Dionysus? Maybe that propionic acid you threw on the monkey's fruit. Bad karma can come from the strangest places.

Just sayin',
S-C

[Jimbo]

LOL! Ya youre probably right. Just worked up a sweat in the snow and wind hauling this shit to the garden and scrubbing everythign down floor to celing with sudsy anti bacterial dishsoap. damn this. So how do I get on Dionysus good side again? maybe ill bring the monkey some banana shine? Wow that will be a test of my will, not punting him across the cage but giving him hooch??? I dunno if I got that brand of kindness in me.

[Jimbo]

Well, not one to leave it alone when shit isint going right, I jumped back on the horse to try and figure this out. My theory is whatever is foaming up overnight is creating some proteins that inhibit yeast, like K1 factor yeast do. When I cooled quick and pitched heavy all was well, when I let it sit overnight it took on a stuborn funk after the foam up that could not be resolved. I also suspect that whatever the bug is, it may be coming from the belgian wheat malt. Belgium is famous for sour beers and all manner of crazy wild critters in the air that make the beer sour. (many strains of lacto, brett, pedio etc etc) So this batch is 50 lbs corn, 15 lbs raw wheat, and 10 lbs barley malt. No Dingemans wheat malt. Its gelatinizing now, when its done Ill cool quick and pitch a half quart of sweet smelling fresh US-05 trub.

[Bu77hed]

Jimbo,
As I read this, the only difference in your batches is the source for the corn. Is there a chance the second corn distributer put something else besides propionic acid on the corn that can't be washed off easily? Do you have a third source for corn? Maybe do a side by side using another corn to see if it's just that second distributor's corn?
I do not know anything about corn or animal feed, or how it's stored, and that scares me some, and so far I've stuck to organic stuff so far. I don't really know if organic is any safer but it sounds safer.

[Jimbo]

Good news, Mondays batch has dropped from 1.053 to 1.015 in 2 days, and goin.

Had a little excitement cookin it up tho.... posted the story in "Tell us about your Mistakes' thread. LOL

[S-Cackalacky]

Slow down?

S-C

[Jimbo]

Hard to say. No airlock bubblin. Just the lid put on loose without the clamp ring. I'll be running it Saturday.

[S-Cackalacky]

Hard to say. No airlock bubblin. Just the lid put on loose without the clamp ring. I'll be running it Saturday.

No man! What I'm sayin' is - maybe YOU should slow down. That whole "mistakes" post reads like a comedy of errors. Jimbo, you've done more in the past week than I've done all year. Inspires me to get busy, but damn man, slow down. One of these days you gonna get your slong hung up in that paint stirrer and you'll be talkin' in a squeaky voice.

Just sayin',
S-C

[Jimbo]

LOL. I can't slow down. Get bored shitless and start pacing and torturing the cat. Ever put tape on a cats paws?

[corene1]

LOL. I can't slow down. Get bored shitless and start pacing and torturing the cat. Ever put tape on a cats paws?

Yep I have! Ever tied a foil ball to their tail?