Copper testing and removal

[benchmstr]

I recently had a thread about removal of the rotten egg smell and I successfully treated it!

Thanks guys!

But it got me thinking about how to test for copper content, and possible removal.

I AM NOT CONCERNED ABOUT MY WINE!!

But how would one test for copper and treat it typically.

 

[Johny99]

I don’t know of a test for home, perhaps a lab service. All the reading I’ve done focuses on not adding too much.

 

[benchmstr]

I don’t know of a test for home, perhaps a lab service. All the reading I’ve done focuses on not adding too much.

That’s why I ask..I haven’t found any articles on testing..just using it to treat

You would think they would have a home test..they have test for water and fish tanks..but no wine test that I have found.

Kind of unusual

 

[Johny99]

Maybe it is a risk issue since cu is a health issue and thus potential liabilities for a test? One thing if you kill some fish, another if it’s your neighbor? I have no idea. Interesting question though as I’ve used cu to correct a couple of batches and it sure would have been nice to know definitively that I didn’t over do it. Please be sure to post if you find something.

 

[Doug’s wines]

Normally you would send to a lab for a gas chromatography, This book has a few ways you can precipitate heavy metals. I’ve never tried them.

https://books.google.com/books?id=tGxiAAAAcAAJ&pg=PA541&lpg=PA541&dq=copper+test+wine&source=bl&ots=mT287F3j4K&sig=-_GTOAoWIKN7PIWxj7-sX8nBDMo&hl=en&sa=X&ved=2ahUKEwjszZrjw77ZAhWO71MKHa7DDuI4FBDoATAAegQICRAB#v=onepage&q=copper test wine&f=false

 

[Scooter68]

I would sorta expect that if you can't determine the safe amount of a chemical to use then you would not use it. Especially if the result of an error could be very serious. I'd rather lose a few gallons of wine than to lose my health, life or someone else's.

 

[stickman]

Milwaukee used to make a portable copper analyzer for wine, the Mi451 Photometer, but it seems to be discontinued.

What's interesting is that fresh pressed grape juice comes in with several ppm copper, maybe 5ppm, and nearly all of that is lost to sulfur compounds generated during fermentation. The copper limit for finished table wine in the US is .5ppm and in Europe it is 1ppm, considerably lower than what comes in with the grapes. What happens if you use one of the new yeast cultures that doesn't generate H2S? Is it possible for the wine to exceed the legal limit of copper if copper wasn't added? Maybe there are other sulfur compounds generated that will precipitate the naturally occurring copper.

 

[pete1325]

Most of us have copper water pipes in our homes........I don't see the concern.

 

[user 36973]

Most of us have copper water pipes in our homes........I don't see the concern.

The difference is that we aren't running acidified liquid (eg. wine) through those copper house lines. Acids tend to dissolve metal.

 

[meadmaker1]

At the risk of being yelled at.
The reason for using copper in stills is that it resists the affects of acid in alcohol while binding with sulfer , delivering a smoother product.
Ive seen enormous cooper vessels in distilleries and brew pubs. ???

 

[sour_grapes]

Just to back up jgmillr's point, here is a chart. Note that the pH of wine is lower than 4. Also, note that this chart uses a log scale on the copper ppm.

 

[user 36973]

The reason for using copper in stills is that it resists the affects of acid in alcohol while binding with sulfer

Yep there is good reason to use a copper still. The copper in the still will react with the sulfites and H2S in the liquid to be distilled and form copper sulfate, which looks like little black grains. I believe distillers tend to use turbo yeast to quickly ferment the beverage, but also produces a lot of H2S due to the fermentation conditions. The copper prevents volatile sulfur compounds from making their way to the distillate.

The dregs out of the still after it is done boiling likely have high amounts of copper, but no one will be drinking that stuff anyway.

 

[Scooter68]

"The dregs out of the still after it is done boiling likely have high amounts of copper, but no one will be drinking that stuff anyway."

As long as nobody posts the phrase "It goes without saying...." That's an invitation to disaster.

That's one reason for this forum - to help people do the right things to enjoy wine making and do it safely. In my time on here, every mention of using copper or copper chemicals has included cautions about the dangers of copper to people and that should continue to be the case. The cautionary comments should be included since new folks are joining this forum all the time. Last thing we want is someone seriously harming themselves or anyone else in the process of wine making AND then that showing up in the media.

It never goes without saying.