Had a H2S problem in my Pinot. Followed Margalit's instructions per his book and decided that 0.3ppm did the trick. However, when I should have added 6ml of CuSO4 to 19 liters, I added 60ml of the 4.1g/L stock solution I diluted for the tests. Bumming. So, question is, how much did I end up adding and what is a best guess on how much Cu is left in the carboy. AND, can the wine be saved?
I am thinking, I added 10x too much. So I must have added 3.0ppm. If
0.3ppm was required to eliminate the smell, then I should have 2.7ppm left in 19L. Way too much. What can I do? Stabivin? Cufex?
Copper sulfate is a poison so if you have any doubts how much you've really added, the safest course is to dump the wine and count this batch as part of the learning process.
I second pp's comment. The only practical way I know to recover from this is to dilute with 9X the amount of wine, and that doesn't seem too practical here lol.
Don't dump that wine yet Joe. The label on my jar of vitamins says........"each tablet contains 3 milligrams of copper (150% of the minimum daily requirement)." If your wine contains 3 milligrams of copper per liter, one 750 liter bottle of wine would contain 2.25 milligrams of copper or just about the MDR of copper. I would drink the wine. But, I would make sure I didn't drink more than 3 or 4 bottles per day. Lum Del Mar, California, USA
haha. I was following this thread quietly until I read your comment and burst outloud when I read about VitaWine. What a great I LOVE LUCY show it was. hahaha.
Are you real sure of the numbers, Lum? I don't have my chem texts with me right now - will check tomorrow - but 3 ppm of copper sulfate sounds pretty high --- anyone know the 'safe' limits of CuSO4? I thought it was in the neighborhood of something less than 1 ppm.
Personally, I wouldn't want to drink wine with anything like 'too much' CuSO4 in it.
At the very least - JG might want to consider bentonite fining the wine in the hope of dropping some copper ions?
I am NOT real sure of the numbers Rick. I am sure of the quote from the label on my vitamin bottle. I am also sure that Bentonite will not remove any significant amount of copper from wine. But, fining with dry yeast can reduce the copper content of wine considerably. Lum
Copper sulfate: To remove hydrogen sulfide and/or mercaptans from wine. "The quantity of copper sulfate added (calculated as copper) shall not exceed 0.5 part copper per million parts of wine (0.5 mg/L) with the residual level of copper not to be in excess of 0.5 part per million (0.5 mg/L). 21 CFR 184.1261 (GRAS)."
Yes, in wine it is supposed to be less that 0.5 ppm.
The 3mg per liter amount is not typically considered critically dangerous, as the human body has a good mechanism for excreting excess copper. But it's not a good idea to challenge your body too much with copper, your body has its limits of coping, and is slow at excreting excess copper. The most immediate issue with too much copper in your diet is that it competes with zinc absorption.
Here's a good summary reference on copper in humans:
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Copper is an essential metal and the daily requirement has been estimated at 30 micrograms/kg of body weight for an adult. Copper acts as a catalyst in the formation of haemoglobin, the oxygen-carrying blood component. Copper is stored in the liver and excreted in bile salts.
Minerals including copper must be bound to a protein to be usable. Biounavailable means the mineral is present, but in a form that is unsuitable for the body. The highest concentrations in body tissues are found in the liver and certain areas of the central nervous system, particularly the brain. The normal concentration of copper in blood plasma is 1 mg/litter. The gastrointestinal absorption of soluble copper is regulated by the need and is usually around 50%; uptake may also take place after inhalation. Elimination of copper is slow and takes place via bile. The chronic accumulation of copper in the body is rare and occurs in Wilson's disease caused by an inborn error of the copper metabolism characterised by a diminished capacity to eliminate copper via bile. This leads to secondary lesions in the liver and the brain.
Copper (Cu) is a heavy metal whose unbound ions are toxic. Almost all of the copper in the body is present as a component of copper proteins, thereby reducing the in vivo concentration of unbound copper ions almost to zero. Genetic mechanisms control the processes by which copper is incorporated into apoproteins and those by which toxic accumulations of copper are avoided. Almost every daily diet contains 2 to 3 mg of copper, only about half of which is absorbed. Any copper absorbed in excess of metabolic requirements is excreted through the bile, probably via hepatic lysosomes. On average, an adult has about 150 mg of copper in the body, of which about 10 to 20 mg is in the liver. The remainder is distributed ubiquitously.
Acute copper poisoning is a rare event, largely restricted to the accidental drinking of solutions of copper nitrate or copper sulphate, which should be kept out of easy access in the home. Copper supplements should be kept away from children. Chronic copper poisoning is also very rare and the few reports refer to patients with liver disease. The capacity for healthy human livers to excrete copper is considerable and it is primarily for this reason that no cases of chronic copper poisoning have been reported.
A high copper intake adversely effects zinc absorption, and thus dosage recommendations for copper are often based on zinc intake. The optimal ratio of zinc to copper is 10:1. Since copper and zinc compete with each other for absorption in the gut, copper toxicity has been the subject of greater concern in recent years. This is primarily due to reduced zinc in the diet and the switch from galvanised to copper water pipes. Acidic water such as rain water, left standing in copper plumbing pipes, can be a source of toxicity when consumed. In prolonged contact with copper cooking utensils, an acidic food or beverage can dissolve milligram quantities of copper, sufficient to cause acute toxicity symptoms such as self-limited nausea, vomiting and diarrhoea. High copper levels, especially when associated with low zinc levels, have been linked to a variety of symptoms and conditions.
Copper is a metal used as an alloy in brass and bronze, as a component in some solders, in pigments such as emerald green, in ceramic glazes, and as a salt in the lithographic process.
Copper salts are irritants to the skin, eyes, and mucous membranes. Ingestion of copper salts may cause vomiting, diarrhoea, hemorragic gastritis, and excessive salivation. Copper sulphate has clinically (medicine) been used as an emetic. It is also used in the whitewashing and leather industry. Toxicity is primarily due to accidental and suicidal attempts, and results in intravascular hemolysis, methemogloninemia, renal failure and often death. Vineyard sprayers using a solution containing aqueous copper sulphate developed granulomatous and fibrotic lung lesions. Inhalation of copper dust and fume results in irritation of the respiratory tract, ulceration and perforation of nasal septum, metallic or sweet taste, and in some instances, discoloration of the skin and hair. The inhalation of metal fumes produced at high temperature, such as welding, may cause "metal fume fever", an influenza-like (benign) illness. High copper content in drinking water and food may contribute to the development of severe liver damage in infants. Copper compounds used by potters are not considered hazardous as well as for pottery users. Copper in glazes fluxed by lead compounds will leach more lead.
For further information, please refer to the URLs below:
Your numbers had me worried so I checked my vitamin bottle again. It still says 3 mg of copper is 150% of the MDR, so I looked at your numbers more carefully.
From above......for a 150 pound person, 30 micrograms/ kg of body weight is roughly equal to
150 # / 2.2 #/kg = 68 kilograms
68 kg X 0.000030 gr/ kg = .002 grams or (2 mg of copper as minimum daily requirement). .003 /.002 = 150% of the minimum daily requirement.
So, the label on my vitamin bottle seems to be reasonable and I wonder how TTB arrived at 0.5 PPM as the limit for commercial wines.
Add dry yeast to the wine, stir, rack the wine off the yeast lees after a week or two.
Apparently, the metal ions adhere to the yeast sell membrane and are removed when the wine is racked off the yeast lees. Old (dead) yeast seems to be as good as fresh yeast, so I always save any old yeast just in case I need it to remove metal ion. I have used as much as 50 grams of dry yeast per
Thanks Lum! I will try it on a small carboy and see what happens. Interestingly, MLF was going along swimmingly until I added the excess copper. It then stopped and I cannot seem to get it going again and I did a chromatography test and it is definitely not finished.
The is a method of reducing copper ions in wine. It is called pottassium ferrocyanide fining. I do not recommend it be used.
Cold stabilisation may help reduce the concentration.
As other people had suggested add yeast hulls.
Also I think that it is best to work in ppm CuSO4.5H20 (copper sulfate pentahydrate) when doing these trials and additions. It is the copper ion which removes the sulphide character. However you cannot buy a bottle of copper ions to add, you have to buy the salt.
The main reason the TTB has a 0.5 ppm limit I believe is because if there is more than 0.5ppm copper ions present in solution in the bottle, then you can have probems with copper casse, the copper drops out of solution.
I made that mistake once too, exactly the same issue too, 10x too much. I did the yeast thing but I also blended it down too, I ended up with
15 gallons of a sort of white zinfandel.
The only commercial white zin I will even drinkg is Berringers, it's less sweet. I made it in that style and it went fast, which was actually a little annoying. (Most people around here like fruity approachable wines.)
Since I give most of those style wines away I took it to a lab to ensure it was under the limit and it was. (I'm not saying you need to do that, just saying the solutions to your problem mentioned by Lum work.)
Lum, So about 10 grams per gallon of yeast then give/take? How long should it take to remove some of the copper? I suspect I will wait until the yeast settles to the bottom. Will it have done the job by then? Its $22 to test a sample for Cu conc. I am thinking about doing a before/after to see how much was removed.
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