Poll for those knowledgeable on methods to eliminate H2S, comments please.

[NorCal]

I was looking at the "how to" information on a wine making supply web site and came across the wine making troubleshooting part of the site and read their recommended procedure for getting rid of sulfur smell in wine.

These steps are included in their recommended procedure

- Buy a piece of copper flashing from a home supply store
- Hold the piece of copper in the neck of the carboy while the wine is being racked, so that the wine runs over the copper surface and into the carboy. Fine and/or filter the wine.

This is counter to what I feel is the proper way to handle this issue, due to the potential excess copper remaining in the solution. I brought this to their attention, sent articles etc, but they are steadfast that this is safe and correct advice. The site has been very responsive and I don't want anything but to have a discussion on this topic by knowledgeable home and commercial winemakers. I will be sending the site the link as well.

If you agree or don't agree, please give a short explanation why.

 

[sour_grapes]

I find graphs like this one convincing:

Note that the y-axis is logarithmic, and that the lowest pH on that graph is about 5.5. Wine is about 100x more acidic at pH of ~3.6.

I cribbed this figure from a 3rd source, but apparently it is from:
"A practical guide for determining the solubility of metal hydroxides and oxides in water," Dyer, James A.; Scrivner, Noel C.; Dentel, Steven K. E.I. DuPont de Nemours and Co., Wilmington, DE, USA. Environmental Progress (1998), 17(1), 1-8.

 

[GreginND]

No-one should recommend using a toxic metal without controls. Ugh.

 

[cmason1957]

I am going to guess that the site you pulled the information from assume that the time the copper is in contact with the wine is small enough, that even though copper is very soluble in wine, it isn't in contact for that long, so maybe it doesn't matter. I am of the same opinion as Greg, without controls there is no way to be certain that the level of copper isn't large.

<BEGIN SARCASM>
On the brights side, they didn't say get several pennies and drop them into the wine until the smell goes away. So they got that going for them.
</END SARCASM>

 

[bshef]

A well known and respected winemaker tells the story of the only wine he ever dumped. The grapes (bought by the winemaker) had been sprayed with sulfur just before harvest. The winery had crushed a portion before he arrived at the crush pad. The smell was prevalent so he had workers wash the remaining grapes. He fermented the sulfur laden must; wrote to winemakers all over the world and no one had a solution to remove the smell. It was dumped. So, I would think if this winemaker could not find a solution, none exists.

 

[4score]

I've always gone by the guidance of not allowing unmeasurable amounts of copper into wine. There are safer ways to approach an H2S wine, like splash-racking, Redulees and Copper Sulfate (carefully measured). I contacted Daniel Pambianchi, renown winemaking consultant and author and asked for his thoughts. His response was, "This is not a good practice because you don't know how much copper is taken up in the process, and excessive copper is not good health-wise and is also an oxidation catalyst. The only way to address H2S quantitatively (if a splash racking did not solve the problem) is to add CuSO4 in very accurate fashion after bench trials to determine the optimal amount needed. There should be no (or very little) residual copper in the wine."

When you think about beer-making, you tend to see more copper usage....but even here, they are trending away from copper. Beer has a higher pH (close to 6), so the copper is an issue but nothing in comparison to the potential issue with wine. As @sour_grapes points out, the soluble copper in wine is exponentially higher.....higher risk.

 

[Johnd]

I voted no for the same reason everyone else does. We painstakingly calculate, measure, and add necessary additives to our wines for a reason, to make sure they're tasty and safe to drink. Why in the hell would I add unhealthy chemicals (copper) to my wine in undetermined and uncontrolled quantities when there are other solutions that offer 100% control and knowledge. I've never had H2S problems and don't plan to, an ounce of prevention (or a few grams of nutrients) is worth way more than a pound of poisonous cure.............

 

[mainshipfred]

I had a case of H2S with my Grenache this year but a good splash rack and return seemed to have taken care of it. Earlier on before I knew about nutrients and copper I had a case of it and did use a copper wire to stir. It did work.

 

[CDrew]

In my brewing days I had a copper coil as a wort chiller. If I ever start again, it will be with a stainless immersion coil. I'll bet the copper works better because of the better heat transfer, but still, don't want to mess with extra copper. BTW-copper is both an essential nutrient and potentially poisonous. It's all about the concentration.

And keep in mind there are a bunch of H2S preventing yeasts out there. I'm thinking that's the future.

 

[Scooter68]

Wish I had a success story to contribute. Had one batch of strawberry that suffered - used a strip of copper sheet metal from Lowe's AFTER I used a degreaser and several washings with dish soap to make sure I didn't add something else to the problem. Unfortunately it was either too late or too far gone.
(never did like the idea of filthy lucre in wine (Copper pennies) just sounded all wrong.)

 

[user 36973]

I brought this to their attention, sent articles etc, but they are steadfast that this is safe and correct advice.

Tell the business that you will be reporting them to the FDA ( then do) and that their advice has opened them up to lawsuits from anyone who has followed it.

And I'm sure the state/county health department would be happy to pay them a visit.

 

[mainshipfred]

Will the following experiment create an accurate measure?

1. In a 7 gallon carboy add enough acid blend to get a solution to pH 3.5
2. Cut and weigh a 100% copper scouring pad to fit in a funnel
3. Gravity rack the solution through the funnel. Gravity racking will leave the solution in contact
with the copper for an appropriate time
4. Weigh the scouring pad after it is dry.
5. Divide the weight difference by 35 to get the mg/bottle.

From what I can tell the RDA or RDI for copper is 1-2 mg. My scale only measures in .01 of a gram so depending on the results may not be terrible accurate but may be close enough.

I'm not advocating the use of copper, just curious.

 

[Ajmassa]

Will the following experiment create an accurate measure?

1. In a 7 gallon carboy add enough acid blend to get a solution to pH 3.5
2. Cut and weigh a 100% copper scouring pad to fit in a funnel
3. Gravity rack the solution through the funnel. Gravity racking will leave the solution in contact
with the copper for an appropriate time
4. Weigh the scouring pad after it is dry.
5. Divide the weight difference by 35 to get the mg/bottle.

From what I can tell the RDA or RDI for copper is 1-2 mg. My scale only measures in .01 of a gram so depending on the results may not be terrible accurate but may be close enough.

I'm not advocating the use of copper, just curious.

Always enjoy a good ol FredLabs study.
The ethanol/boiling study. Then the Dissolved O2. Copper leaching on deck! Btw the idea to check by weight before/after is damn clever.
(And only a matter of time for that ‘Oak surface area/time to neutral’ study!)

 

[NorCal]

Great idea. 1,300 micrograms or .0013 grams per liter is considered the maximum allowable level. Pour 7 gallons through ten times is 265 liters would give a measurable .34 grams.

 

[winemanden]

Fred, I had one smelly 22 litre brew quite a while ago. Bought a couple of copper pan scourers (Looked like flat woven wire mesh) from the hardware shop, popped one into my funnel and splash racked the wine through it. The copper mesh turned black but the wine lost the stink, tasted great after ageing. I'm still here and feel fine. I don't know if it was the copper or the racking maybe both. No science but it did the trick.
Regards to all.

 

[NorCal]

Fred, I had one smelly 22 litre brew quite a while ago. Bought a couple of copper pan scourers (Looked like flat woven wire mesh) from the hardware shop, popped one into my funnel and splash racked the wine through it. The copper mesh turned black but the wine lost the stink, tasted great after ageing. I'm still here and feel fine. I don't know if it was the copper or the racking maybe both. No science but it did the trick.
Regards to all.

There is no question that copper will remedy H2S, it’s proven. It works because copper will leach into the solution at the pH of wine. The copper that combines with the H2S will fallout, any excess will remain in solution, thus the reason to thoughtfully only add the copper necessary to remedy the issue and not blindly add not uncontrollably add to the wine.
For me it’s the winemaker that makes 100’s of gallons each year, has H2S constantly and uses this process as their remedy. Over the years of drinking wine with excess heavy metals can pose a health risk for some people. If you take the time to research it, it’s just bad advice.

 

[NorCal]

Just a follow up. I contacted the Minnesota Department of Health and forwarded the information along to them, including a link to this discussion. The technician I spoke to agreed that this was an unsafe recommendation and had the division that regulates/permits that company make contact with them. If took a few months, but I noticed today that they re-wrote the page on how to treat H2S and eliminated the recommendation that you add an uncontrolled amount of copper into your wine by running the wine over copper flashing from the hardware store.

Who knows how many people took this bad advice. They were adamant that their recommendation was safe and correct, but I'm glad to see they were persuaded and remove the recommendation, shown below:

- Buy a piece of copper flashing from a home supply store
- Hold the piece of copper in the neck of the carboy while the wine is being racked, so that the wine runs over the copper surface and into the carboy. Fine and/or filter the wine.

 

[user 36973]

Good job!

 

[wildhair]

This was the first time I ran into the "rotten egg" smell in any of my wines. I'll have to go back and look at the yeast I used in this black raspberry - think it was RC-212 - to see if that may have been a factor. I used the splash racking, didn't help much. Then whipped it up with a whisk I made from copper wire and that cleared it up. Got the info from this site, actually. I read all of the above posts and understand the risk with an "unknown addition" of copper, but since I'm not a commercial winery, and I certainly don't do this to ALL my wines, I'm not really all that concerned about copper poisoning. There are a lot of other far more worrisome things in my hemisphere.

 

[user 36973]

I'm not really all that concerned about copper poisoning

You will be when you overdose with copper and spend the afternoon throwing up