Left Copper in Wine, Dangerous?

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1galbrewer2

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I had removed some remaining sulfur smells from last year's wine with a copper wire. Turns out I forgot about it. Is it still safe to bottle and drink?

I know copper sulfate can be potentially dangerous, but my understanding was that by using a copper pipe or wire you avoided this danger. Is this the case, or is there a potential danger to having left copper in wine for a year? Thanks in advance.
 
There is potential danger. Many metals, including copper, can dissolve into acidic solutions like wine. With the copper being in the wine for a year there was ample time for an unknown and potentially elevated quantity of copper to accumulate. I would dump this batch, or distill it if you really don't want it to go to waste. The copper salts *should* remain in solution and not distill over.
 
Alright, I have decided to dump it. It’s a small amount. Anyone wanna volunteer their thoughts on tasting the wine and spitting it out?
 
I would taste the wine but not the whole bottle and definitely not the whole carboy. and Yes if you feel better spit it out. ,,, Remember in the old days bronze was all humans knew how to make. Remember in the modern days water is run through copper pipes in homes.
Some copper is required for human nutrition, just not a lot.
 
I was asking for safety reasons. I was just interested in tasting how the wine came out, not tasting if there is copper in it.
My reply was terse and unfortunately cryptic.

Copper is highly poisonous. It isn't worth messing with.

For future reference, do not use metallic copper to treat a wine. If you have H2S, buy a product like Reduless, which provides a measured dose of copper that ensures no overdosing. Also follow the directions, as mine indicated the wine needed to be fined a while after treatment to ensure the copper was precipitated.
 
Copper sulfate solution can work too if your LHBS doesn't carry Reduless, and you're careful in measuring. I had bought some "just in case" and I used it for the first time on some Tempranillo rosé this year that had some H2S smell even after splash racking with the All In One. Just a half mL of 1% solution into 3.5 gallons (about 0.1 ppm) was all it needed.
 
Agree with the others here. I believe the Legal limit in the US for Copper residual concentration is 0.5 PPM. a lab can do spectroscopy on it to see if it has unsafe levels but it's probably not worth the cost (~$40 - 80 plus shipping) if it's a very small amount. I had to treat a Tempranillo red with it last year, and after bench trials, I added 0.5ppm; I then let it settle and filtered it through a Buon Vino #2 filter after to ensure no elemental copper was transferred. I had the Cornell Craft Beverage Laboratory test it and the concentration was somewhere in the 0.13 ppm range for the sample i sent them.

https://cals.cornell.edu/cornell-ag...rage-production/craft-beverage-analytical-lab

https://cals.cornell.edu/cornell-ag...erage-analytical-lab/wine-hard-cider-analyses <-- methods

they do atomic absorption testing for around $45 for a single ion (copper).

They were very good when I used them and I highly recommend them if you ever do want to confirm anything. I wanted to make sure my red wine wouldn't be toxic, and that piece of data gave peace of mind.
 
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