Diagnosing bad washes and salvaging bad spirit run output

AceNZ

I've done two washes recently that seem to have gone terribly bad in some way.

The first was a wheat germ + sugar wash. The second was barley + simulated raw sugar (modified Aces Neutral). Both times, I used EC-1118 yeast and carbon-filtered city water. I keep detailed logs and can provide more info if it would be helpful.

I pot-stilled them separately (with all-SD gear). Both had a stripping run first, followed by a spirit run.

The problem was a very "yeasty" (for lack of a better word) smell and taste that strongly smeared through all of the product output, whether measured ABV was 65% or 15%. There were never any "real" hearts (or even any distinct boundaries between cuts). The output was completely transparent both times; no cloudiness. The second wash ended better than the first before stilling, but it was still bad. On the second spirit run, I ran a drop or two per second for fores and heads. I'm not sure if it helped or not; the would-be hearts were still undrinkable.

1. My best guess is that stressed yeast were the problem. Does that sound right? If so, is there a way to tell what the most likely cause of the stress was? Are there other ingredients or potential process problems I should look at? Or things to watch for or be more careful about?
2. Any guess about what this smelly chemical might be? It's not green-appley like an aldehyde, or pear-dropy like ethyl acetate, nor is it stinky like a dirty aquarium, nor a burnt type smell, nor fruity like an ester.
3. I'm in the process of setting up a new VM/LM column with SPP. Are these old runs likely to be salvageable that way? Or perhaps usable for a cleaning run? Or are they more likely to smell / gum up my SPP packing? At the moment, the most likely use is as weed killer.

grim

Does it smell like phenolic or plastic, maybe slightly rubbery? Was your yield lower than expected? Those two are always telltale signs of infection for me. Not sure if you logged your total yield, but did it seem that you started with a high ABV and then suddenly dropped off? Beer guys tend to name it more of a "band-aid" smell (more commonly noticed with brett), but that might not be something globally recognizable.

Two back to back with different washes can sometimes point to some of your mashing or fermenting equipment harboring some nasties. Were both back to back? What's your sanitation protocol like?

If not infection, second guess would be - Are you stilling on elements? I've had a few washes that had more solids than I'd like, and they burned on the elements. However, the resulting off-flavor didn't at all seem like a charcoal/burnt odor, but more of a plastic smell.

punkin

Circuit boards.

AceNZ

It doesn't remind me of the phenolic compounds I'm familiar with. It's not plastic or rubbery, nor does it remind me of Band-Aids. It's not a sharp or acrid smell, more dull, and I can't smell the alcohol through it. If it was isolated to heads or tails, it wouldn't bother me; it's the broad smearing that's disturbing.

The yield was about what I expected, and I don't think the ABV dropped off particularly sharply.

Yes, these runs were back-to-back, but they were also the first runs with new gear.

Sanitation protocol: for the first run, washed the then-new stainless fermenter with dish soap to remove any residual manufacturing grime. Then rinsed and soaked it in diluted Star San. Then washed again with dish soap, rinsed very thoroughly, and rinsed again. Hydrometer that was dipped into the wash was also cleaned with dish soap and then rinsed thoroughly. No bleach.

For the first batch, I covered it with a muslin cloth for the first hour or so, then put the stainless lid on, vented through a silicone blow-out tube into a small jar of water with a little sodium metabisulfite in it. Didn't use muslin on the second batch.

The boiler has exposed elements. The first wash was filtered through cheesecloth, but was still cloudy. I could see light charring on the elements afterwards (though the elements were never above the liquid). The second wash was clear, but had the same smell, though not as harsh.

AceNZ

I was reading the descriptions here.

The "day old (liquid) bread" smell seems closest; it fits with my earlier "yeasty" description -- both are more "reminds you of" type descriptions than exact.

That page suggests the smell is oxidized aldehydes, which might fit, too. I did smell the green apple odor of aldehydes early in both washes, but it went away by the end. I have actually been giving the wash a good mix after racking, to drive off CO2 and hopefully speed-up clearing. Maybe it's too much?

Based on my other reading, limiting oxygen exposure seems like an odd fix. Have I missed something? Wouldn't it be better to prevent aldehyde production in the first place?

Rpman2

I'm planning on putting some Oaked bourbon I did in my early days in my next spirit run because it tastes a bit yeasty. Is this a good plan or should I just chuck it.

Topshot

@AceNZ - How is your pot still set up, have you got a picture?

Rpman2

It's on a dash 2 4 inch. Gonna run it with 4 bubble tees with a 50 litre milk can boiler

Rpman2

Sorry forgot to mention no water on the deflag just on th PC. Will post pic when I get home.

Topshot

Do you need to add the deflag, or is it just for height?

grim

If you have enough to run it through once more before adding, I'd suggest going that route. I don't know what your defect is and how strong it is, but I'd always be cautious about spoiling two batches. There are volatile defects that can't easily be stripped out, if you are in this category, you are in for disappointment. If you don't have enough for it to be worthwhile, try a pass through some carbon to see if you can pull the defect out. You don't need to worry about getting it clear post carbon, it can be dusty.

If you've already given it a try, maybe it's worked out well. That's the thing, you just never know until you try.

AceNZ

@Topshot said: AceNZ - How is your pot still set up, have you got a picture?

It's a pretty vanilla SD setup:

Topshot

@AceNZ - Nice, how much power do you put through on the run and what's your product flow rate. Do you run the water flat out?

CothermanDistilling

@grim said: Does it smell like phenolic or plastic, maybe slightly rubbery? Was your yield lower than expected? Those two are always telltale signs of infection for me. Not sure if you logged your total yield, but did it seem that you started with a high ABV and then suddenly dropped off? Beer guys tend to name it more of a "band-aid" smell (more commonly noticed with brett), but that might not be something globally recognizable.

Two back to back with different washes can sometimes point to some of your mashing or fermenting equipment harboring some nasties. Were both back to back? What's your sanitation protocol like?

If not infection, second guess would be - Are you stilling on elements? I've had a few washes that had more solids than I'd like, and they burned on the elements. However, the resulting off-flavor didn't at all seem like a charcoal/burnt odor, but more of a plastic smell.

brett is more 'barnyard' or horseblanket, and can be very desireable in some beer styles... hard to get from an infection unless you deal with wood or brett beers (brett naturally lives in wood)

Band-aid (old school bandaids, not new ones) is chlorophenolic, I am extremely sensitive to this one, it is 90% chance from a bit of chlorine still in the water...

yeasty is just that...

in this wheel, yeasty is next to cooked vegetables, which would be DMS, which primarily comes from not cooling wort quick enough.

Help me understand the beer flavor wheel @ HomeBrewTalk

AceNZ

@Topshot said: AceNZ - Nice, how much power do you put through on the run and what's your product flow rate. Do you run the water flat out?

I'm using a single 2.4 kW element with a variable power controller.

Product flow rate varies depending on what I'm doing. For stripping, roughly 2 L / hr.

Yes, I run the water flat out. The tiny beige 12VDC pump is connected to the blue tube on the far left of the photo.

punkin

Pretty yes, top of the range for it's size, yes. Vanilla, no. :D