Copper chemical reactions?

Whitecap

@Mickiboi, you reminded me I used a couple galvanized steel fittings on the drain valve while waiting for an order of 304ss fittings to come in. I forgot about it until your story. I'll replace for the next run.

Smaug

Just bumping this.

Joel did you every resolve this mystery?

Redwun

Anyone still follow the thread. Did anyone figure out the substance? I've had the same thing happen a few times will upload some pictures.

1. The first time it happened was about 2 years ago all grain mash that we made and it only fermented about 50-75% couldn't get it to go more so assume there were starches and unfermented sugars left as always and def solids we def didn't get full starch conversion so were a lot of starches in wash. Still was about 95% full probably too much but ran it slow to try to get what we could out of it. After we saw the residue were a little concerned and decided to dump it all.
2. Second time was a strip run on all grain beer "Double Wench" kegged from a local brewery. First 2 pics of inside still head were from the kegged beer, clean no solids, we ran last week. Still was about half full.

The paper towel with wipe samples are from the first batch we had it happen of all grain mash and Def not a clear wash.

Ponderous...

CothermanDistilling

I think it is something in hops... I had it a lot when doing gifted beer...

Smaug

@CothermanDistilling said: I think it is something in hops... I had it a lot when doing gifted beer...

Jeff at Moab reckons the a low sulfur yeast helps and also a diacetyl rest.

jbierling

Definitely not just from hops. I had this with traditional grain mashes (no boil) with no hops.

I've always felt this had something to do with burning/overheating occurring in the kettle. This problem almost completely disappeared after switching to a baine marie/double boiler.

grim

Someone over of ADI said they sent it to a lab, but never posted any results.

My money is still on some kind of zinc compound.

We see this regularly running grain-in on the big steam jacket still. No hops, no electricity.

DonMateo

I get his kind of silvery gunk on the inside of my copper helmet and chimney regularly from grain on distillation, or at least not filtered straight from the fermenter distillation. One solution, which has worked a bit, was I put a strainer section below my copper helmet and put copper mesh under in the strainer section and use that copper mesh to block the gunk going up the helmet. I think it works very well as every 2 or 3 runs when I take apart my helmet and chimney for cleaning the mesh is completely black and in some cases partly degraded. I put the mesh in Citric acid to clean up the gunk and that worked to get the copper mesh back up some kind of shiny copper look. It didnt stop the black gunk on the inside of my helment and chimney but I think it reduced it a lot.

jbierling

@DonMateo locking the silvery stuff doesn't work, it will accumulate on any copper in the vapor path.

@grim, didn't know you'd seen this too. It's unlikely you'd burn anything with steam.

The mystery deepens. We don't know much other than it's probably something in the grain.

punkin

Ever thought about writing to John Palmer?

Redwun

Yes, the mystery deepens and continues.. going on years now for many, how many countless hours reading online with no real definitive answers yet.

I heat with propane, had no burn evidence and use no electric.

I think we can probably rule out electric for the most part IMO, yet nothing can be 100% at this point.

To me it seems like it has something to do with grain/ yeast, the mash maybe some oils and possibly the foam up or puking up froth probably in the tails i would guess.

Strange that we have millions of distillers and no one knows the real answer, I'm going to find out! As with most here I cannot afford hundreds let alone thousands of dollars for expensive lab samples. Any pro bono labs willing to assist, I'm determined to find the science behind this. Maybe in the future I/we could collect samples from all who are willing, send to a willing lab or labs for analysis or if we have enough people willing to donate some funds to help the cost. Just a thought.

I found this link here: Re: Metal flake in pot still @ HD

OK now this happened to me, strange gas fumes coming out before and during the drip possibly CO2? And others, almost exactly what it looked like on the first batch that it happened a few years ago on that stuck ferment mash batch I ran rye corn barley was going to be a bourbon.

On a side note some other interesting info here on alcohol cloudiness, you may all have already seen:

Malt Maniacs - CHILL FILTRATION AND CLOUD FORMATION IN WHISKY (PDF)

Cheers
:D

jbierling

Its normal to off gas at the start of distillation. I think much of the vapor is co2 (puts out a match). Fog/smoke is often burning.

jacksonbrown

Maybe do some reading in the IBD resources.
We got it from single malt mixed with verdigris and what I called 'whiskey fat'.
We called it ash but it wasn't a result of burning.
I'm not suprised modern American forums don't have much but the old resources will have something.

grim

The bottom plate right above the wash has the largest amount, see very little by the 4th plate. My DIY copper catalyzer above the dephleg sees zero accumulation.

This study is the reason I think it's Zinc.

Investigations into the Use of Copper and Other Metals as Indicators for the Authenticity of Scotch Whiskies (PDF) @ Wiley Online Library

grim

Look at the Zinc concentrations relative to everything else:

grim

Magnesium probably number 2.

Effect of wheat malt on the concentration of metal ions in wort and brewhouse by-products (PDF) @ Wiley Online Library

jacksonbrown

I've had it with rum and wine runs too. Maybe more likely on acidic washes? My gut feeling is it's some sort of crystallized wax or other entrained solids making their way through.
Further digging on the term verdigris should get close.

I did find the following PDF that talks about the make up of what's there, but not the silver component specifically:

Whisky Verdigris Analysis (PDF) @ Boston Apothecary

I did something similar a few years back separating, washing with EtOH and filtering the gunk out of a whiskey still and got three main fractions. Some green stuff, some black stuff (which I think is the same silver scale here) and a bottle of yellow oil that smells like the essential oil from the world biggest bender.

grim

There are metals in molasses as well.

The other potential factor is yeast.

grim

The verdigris paper is interesting, but I really wonder if that's an artifact of continuous distillation rather than batch.

jacksonbrown

I really don't thinks so. Cleaning the vapour path of a pot still in Scotland is a foreign concept and scares the shit out of distillery managers. Most low wine receivers that aren't fully emptied are full of that gunk and it shimmers like fools gold when you stir it up.

crozdog

I ran a whisky wash the other week through a few plates and a copper product condenser. The plates were silver as and the spirit coming out of the PC was oily and dirty. Had to put a cloth in a funnel under the output to collect the crud.

The wash was out of a brewery, not boiled and had was fermented off the grain.

@grim where do you think the zinc is coming from? The only things I can think of are the barley itself, or possibly yeast nutrients.

jbierling

Beer (grain) does not typically need yeast nutrients.

jacksonbrown

Zinc chloride is a pretty common addition but the amounts are miniscule.

DonMateo

@everyone. Thanks for this discussion. I am glad its not just me that gets this shit in the inside of my helmet.

jbierling

I’ve had silver on copper mesh after 5 plates and reflux condenser.

Glenndog

I have had these silver deposits on the first three plates ever since I bought my still nearly five years ago. I only run molasses wash and I use refinery molasses (fancy Molasses) mostly but the same happens when I use C grade molasses as well. I just live with it but I do believe it's the wash causing it. No pitting of any part has occurred over that time.