Wednesday, November 28, 2007

Change of Heart

Just when I am warmly wrapped in my self security; just when I know exactly what I think about an issue; just when I have made up my mind, along comes a fact to slap me back to reality.

In my last blog entry, I stated the following: “I’m for the Nutritional Facts labels—I am not so sure about the Ingredient labels.”

Not any more, not since a story broke recently concerning copper in a New Zealand wine.

An unidentified German company declined to accept a shipment of bulk wine from New Zealand because it contained 3.6 parts per million of copper; in Germany, the maximum is about half that, but in New Zealand the maximum is 5 parts per million. According to any thing I’ve read, the New Zealand maximum seems way too liberal. In the U.S. the feds set the maximum under 1 part per million.

The human body needs copper as a trace mineral, but it definitely doesn’t handle copper too well in large quantities. One of the serious dangers is liver damage; one of the milder yet discomforting dangers occurs when copper is out of proportion to other trace minerals in the body: heart palpitation, which reminds me of something I read a few weeks back.

A researcher in Berkeley, California claims to have developed a computer gadget that can analyze the wine in your glass for potential allergens connected to biogenic amines (histamine, tyramine, etc.) This fellow said that he got the idea while researching biogenic amines and connecting his heart palpitation when he drinks red wine as a reaction to the amines. Well, maybe he drinks too much wine with copper in it!

Anyway, all of this has made me rethink my position on Ingredient Labeling. (You see, even the self-secured are prone to doubt—we don’t tell people, except that I just told you.)

When I wrote about the labeling issue I stated that not much is added to wine. That was both true and misleading. If you add a substance to wine that is dangerous, what does it matter that you don’t add much else? Copper is added to wine, but not routinely—I hope!

To be brief, wine is subject to the formation of hydrogen sulfide, especially when the juice may have come into the fermentation tank with a nutritional imbalance. During fermentation, the yeast plays a role in converting and releasing compounds and when conditions are right on the nutritional scale, hydrogen sulfide can be one of the results of that activity. Also, high residue of sulphur from spraying grapes against disease during the growing season can cause hydrogen sulfide to form in wine.

This form of sulfur is not to be confused with sulfur dioxide which is commonly called "sulfites" on the warning label.

You know that party trick: you have a glass of wine in front of you that smells like an old egg and when you drop a penny into the glass the rotten egg smell vanishes? That’s what copper does to hydrogen sulfide.

Sometimes when hydrogen sulfide forms in wine, it can be released by simple aeration. Sometimes the winemaker can simply stir the wine with a copper rod.

It’s been reported, but not accepted outright, that the airtight nature of screwcapping causes another problem connected to sulfur compounds.

The progression of hydrogen sulfide can lead to a more serious problem known as “reduction,” which takes that rotten egg smell to odoriferous heights. The reason a winemaker aerates to fix the hydrogen sulfide problem is that the sulfurous compounds in wine cane be subdued in the presence of enough oxygen. But bottled under screwcap, wine is supposedly in a vacuum and that means the sulfurous compounds in the wine would be starved of oxygen—reduction might take place.

Some, including the respected Jamie Goode, who’s on my blog roll, have accused wine producers of adding copper to their wines before screwcapping the bottles. If Goode and others are correct, and wine producers are adding copper before bottling under screwcap as a preventive measure, the science says that they are dead wrong: the dangers of copper are high enough that adding it should be as a curative only, and a finely-tuned measured one at that.

Since that New Zealand wine was a bulk product—read, cheap—it may have been a wine needing a fix, and that would explain the copper. Still, it does not explain the high level, since, by all accounts that I’ve read, it takes a lot less copper than 3.6 parts per million to fix hydrogen sulfide or reduction problems.

There’s another possibility, however, for the high copper addition: New Zealand has been in the vanguard of the screwcap revolution. Perhaps, their wine industry has taken to dumping copper into wine as a preventive measure. Scary.

In any event, if copper is allowed in wine (and at higher than necessary levels) the next question is what else is allowed?

Believe me, you have no idea how difficult it is for me to say this: Ingredient Labeling may be the right thing for the wine industry to do.

If anything, Ingredient Labeling might serve to make certain wine companies (and wine industries) act responsibly. As an aside, it might help certain researchers suffering from heart palpitation to look in all directions for the source of the problem rather than to make assumptions and then invent a gadget based on the assumptions.

NOTE: I wrote last time about an organization’s blog that has plagiarized some of my blog entries and that I have contacted Google AdSense about the matter. I haven’t heard from Google, but I could not load up the blog this morning. Until I hear further: There’s an organization operating a blog that sells health products to consumers—it goes by the name Healthfullup. Through the RSS feed, this blog lifts and prints my copyrighted material in its entirety from, without my permission and without paying compensation.

Copper Story

Wines&Vines EuropeanCommission

Copyright, Thomas Pellechia
November 2007. All Rights Reserved.


  1. Hey Thomas,
    Quite interesting it seems the chemists never stop finding odd things to do. This is why I like to know the wine maker and why smaller producers are better. The best wine is the wine that is least messed with in my experience. The bigger the lot the more the problems that can arise the easier it is to justify using additives of a less moral character. Like Sulphric Acid to lower the PH, it is illegal but undetectable and gives a full mouth feel at the same time! Yes that is battery acid!

    An excellent article! Keep writing!
    Also I hope they stop those thieves from stealing your stuff that is just wrong!

  2. Wine limo,

    Just to be clear, copper is used even at small wineries when hydrogen sulfide is a problem. They'll never let you know because they don't have to.

    When I produced wine at my small winery, I had to use copper sulfate once in eight years. Of course, I kept its use at a minimum.

    Also, from a chemistry standpoint, sulfuric acid in wine in tiny amounts is not unnatural. In fact, the French used to measure wine's natural acidity by way of its sulfuric content.

    Sulfuric acid doesn't have to be added to wine to lower pH, but it is created by reaction to other additions to wine.

    In truly tiny amounts, sulfuric acid is harmless. Essentially sulfuric acid is sulfur dioxide and hydrogen peroxide.

  3. Hello Thomas,

    Regarding your comment "In fact, the French used to measure wine's natural acidity by way of its sulfuric content.
    This is not correct. The French measure total acidity such as everybody else by titration with a strong base (NaOH). They choose to express it as sulfuric acid, such as we express it as tartaric acid in spite of acidity been made up of a a variety of organic acids, including tartaric and malic acids. The titration measures the entirety of carboxy groups, not specific acids, hence the need to express it with one specific representative. In wine (except for France) this is tartaric acid, in cheesemaking lactic acid, in vinegar making acetic acid. It does not mean that there are, in fact only these acids present.

  4. Aha! You got me.

    Change the word "measure" to "express" in my post and I think it's fixed.

    What took you so long and who are you? I have a problem conversing with thin air. ;)