Some mistakes.

[higgins]

I got started in this hobby almost 2 years ago after 26 years of AG brewing. After 13 AG batches of bourbons, single malts, & irish that have been rather good, my last bourbon left me quite disappointed. I used feed corn in my first few bourbons, then food grade cornmeal the last 4 or 5 batches. For this last one I went back to cracked feed corn.

The recipe
1 qt (.95 L) backset
25 lbs (11.3kg) cracked feed corn, mealed
7.5 lbs (3.4kg) mealed rye (not malted)
4 lbs (1.8kg) distillers malt
htl aa, ga, fs917 yeast

My typical process is:
boil water, add mealed corn, mix, add htl aa, mix, rest around 175F (80C) for 3 hrs, power mixing a few times.
starch test, then move it to 30 gal (113L) hdpe drum and drop it to 150F (65C)
add rye & malt & 150F water, mashing at 146F (63C) for a few hours.
add liquid gluco and chill to 90F (32C), pitch yeast
I usually net about 20 gal (75L) of 1.060-65 wort.

Then as soon as I move the corn mash into the hdpe drum, I start boiling water for a 2nd mash.
I'll do 2 mashes, 3 strips, 1 spirit run to net somewhere around 1.5 - 2 gal (5.7 - 7.6L) hearts at 125p, just enough for a BadMo barrel & 1L white dog.
So far I've been happy with the results.

On this last one I decided to do a separate beta-glucan rest on the rye. I mixed the rye & 1 lb (.45kg) malt with 118F (48C) water and rested at 104F (40C) for 30 min. Then I added this to the corn, added the remaining malt, adjusted to 150F (65C) and let rest for a few hours. The b-g rest seemed to work well as the mix wasn't gummy at all. starch test was negative.

MISTAKE #1: Once the second fermenter was filled I wrapped them both in a heavy blanket and went to bed. When I got up in the morning they were both at about 95F (35C), but were already spontaneously fermenting. I pitched the yeast hoping that it would outpace the existing bugs. Should have stayed up a few more hours using my wort chiller to cool the wort and pitch the yeast

I had two 25 gallon (95L) fermentations going, and after a week one had dropped from 1.061 to 1.000, while the other one only got down to 1.030. And there was a mild funky aroma going on - sort of a vomit-like smell. The wort was very yellow and oily, much more so than previous bourbon mashes.

MISTAKE #2:I figured that one ferment was done, the other was stuck. Since the first one was finished, I figured it was healthy and I could use it to get the other one going again. So I mixed the two together (move 5g from one to other, mixed, moved 5g back, mixed, repeat). After another 3 or 4 days one was at 1.000, one at 1.012. I called it a success and went ahead with stripping. I probably should have used the one that finished at 1.000 and tossed the other one.

Stripping and spirit runs went fairly normal, but that distinctive aroma carried over into the low wines and spirit. So now I've got about 2.5 gallons of spirit (before cuts) with a pretty obnoxious aroma.

After a few hours using google search on this site, I think what I had is a butyric infection. There were some references to treating the low wines, some using sulfuric acid to induce a Fischer esterification, and another reference to treating with baking soda. But they were rather short on details.

I was thinking of putting the distillate into one container, dilute to 25%, then treat with baking soda or pickling lime to see if that helps, re-stilling after. Could anyone suggest how much soda or lime to use? Do you think it might work? Alternatively, would refluxing into neutral remove that aroma?

[Ben]

Yep, you nailed it. Butyric, due to the slow cool. You can also boil to kill the Clostridium bacteria so they don't form it.

Treatment: I have been successful with baking soda in low wines, I treated approximately 3 gallons with a teaspoon of baking soda. It takes a few days to fully react. Smell was still sort of there so I hit it again, vomit is gone, replaced by a pineapple thing. I have done this on 2 batches so far, but traced it to a specific bag of crimped barley. Any time I use crimped barley now I sparge and boil, no problems since I started that.

If all else fails reflux it. But you aren't risking much attempting the baking soda treatment. I know nothing about the sulfuric treatment. You may also be able to get it to esterify with a long hold at ≈60°c.

[higgins]

Thanks, Ben.
I've combined them into a corny and topped off with water. I've got 5 gal at 28%. I'll start with 2 tsp baking soda and leave it for a few weeks.

I originally posted this in 'Tell us about your mistakes'. But with the restore it somehow became its own topic.

[higgins]

SCD pm'd me and said he moved it. No problem.

I re-ran this today. The nasty vomit aroma did indeed change to a pineapple like aroma (I actually used 1 tbsp in 5 gal). I now have a triple distilled bourbon. Once I make cuts I'll probably split it into quart jars with 1 toasted/charred white oak stick in each.

I'm still considering this to be experimental, so don't want to use a Badmo.

[shadylane]

SCD pm'd me and said he moved it. No problem.

Another example of our mods hard at work.
I'm guessing he moved it so it wouldn't get lost, and you would get answers.

[NZChris]

It's best to let it convert to Ethyl butyrate while it's still in the fermenter. Doing nothing works as well as anything else, just keep smelling it until the vomit is gone, only takes a few days.

Knocking acids out of solution by raising the pH is best left for making neutrals or for making lime salts for rum essence. I suspect it would knock a lot more than just the vomit smell out of a whiskey.

[Ben]

In my case the vomit smell was tenacious, I let the ferment go an extra month, ran it, let the low wines sit a month, ran it again, still there... the baking soda was a final attempt at salvage before running it through all the plates. The batch did turn out well in the end, I did still find a hint of the smell in the middle heads, this sat for at least 4 months after the baking soda treatment prior to that run. Perhaps my storage area is too cool?

[Twisted Brick]

MISTAKE #1: Once the second fermenter was filled I wrapped them both in a heavy blanket and went to bed. When I got up in the morning they were both at about 95F (35C), but were already spontaneously fermenting. I pitched the yeast hoping that it would outpace the existing bugs. Should have stayed up a few more hours using my wort chiller to cool the wort and pitch the yeast

+1

I've only let one all-grain batch cool overnight (ran out of energy) and found it happily bubbling away in the morning. I pitched right away and luckily the yeast took over.

[shadylane]

+1

I've only let one all-grain batch cool overnight (ran out of energy) and found it happily bubbling away in the morning. I pitched right away and luckily the yeast took over.

I've done the same, but sometimes unsuccessfully.

Now days if I can't stay up long enough for the mash to cool.
I'll pitch bakers yeast at temps as high as 130f.
By morning the fermenter will have a cap and be going like hell.
Yeast can take a lot of heat at first, before there's any alcohol present.