Sulfide aroma (sulfur, rotten egg) - prevention and removal

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RPh_guy

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Over the last several weeks I've researched and written a comprehensive article about the prevention and removal of hydrogen sulfide (the source of the common rotten egg aroma) and related volatile sulfur compounds.

Hydrogen sulfide - Modern Brewhouse wiki

If any experts wouldn't mind taking a look, I would appreciate any feedback. If you are learning, have a look so you can be an expert, and please let me know if something is difficult to understand.

Also, if anyone would like to see more articles like this, any help researching or composing articles would be appreciated. Otherwise it'll take me years to "finish" all the articles that are needed. It's a wiki so anyone is able to edit at will.
Cheers!
 

sour_grapes

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Nice article! Really good to see. I haven't looked at any other pages yet, but this Wiki could be a really useful resource.

I fixed one small typo -- can I get a gold star? :)
 

cmason1957

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One comment and I didn't read everything, just skimmed, but looked like great information. The last three bullet points under copper seem a bit confusing.
  • Copper sulfate pentahydrate: 1g = 0.255g copper
  • Copper citrate hemipentahydrate: 1g = 0.353g copper
  • Kupzit: 50g = 1g copper citrate = 0.350g copper

I don't have a better way to present it, what I think it is trying to say is that 1 gram of Copper sulfate Pentahydrate contains 0.225 g of copper.
 

RPh_guy

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Nice article! Really good to see. I haven't looked at any other pages yet, but this Wiki could be a really useful resource.

I fixed one small typo -- can I get a gold star? :)
Thanks! Every little bit helps.
One comment and I didn't read everything, just skimmed, but looked like great information. The last three bullet points under copper seem a bit confusing.
  • Copper sulfate pentahydrate: 1g = 0.255g copper
  • Copper citrate hemipentahydrate: 1g = 0.353g copper
  • Kupzit: 50g = 1g copper citrate = 0.350g copper

I don't have a better way to present it, what I think it is trying to say is that 1 gram of Copper sulfate Pentahydrate contains 0.225 g of copper.
Does this look better? (I changed it already)
  • 1g copper sulfate pentahydrate contains 0.255g copper
  • 1g copper citrate hemipentahydrate contains 0.353g copper
  • 50g Kupzit contains 1g copper citrate, which contains 0.353g copper
 

cmason1957

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Thanks! Every little bit helps.

Does this look better? (I changed it already)
  • 1g copper sulfate pentahydrate contains 0.255g copper
  • 1g copper citrate hemipentahydrate contains 0.353g copper
  • 50g Kupzit contains 1g copper citrate, which contains 0.353g copper
Yes, I completely understand that presentation without really even having to think about it. There probably should be a mention of Reduless in the alleviating problems section.
 

RPh_guy

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Great!

That's a good idea; I had forgotten about Reduless (even though I've used it). I'd like to be able to offer better advice regarding these products but I couldn't really find any information comparing straight copper sulfate vs Reduless vs Kupzit besides what the manufacturers say.
 

cmason1957

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Great!

That's a good idea; I had forgotten about Reduless (even though I've used it). I'd like to be able to offer better advice regarding these products but I couldn't really find any information comparing straight copper sulfate vs Reduless vs Kupzit besides what the manufacturers say.
I have never seen a write-up about Reduless either, besides manufacturer info. I had to use it once and it seemed to work, probably the best thing to say about it is pre-measured safe amount of copper to use and maybe it includes deactivated yeast hulls also, I think.
 

Paolo_pin

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Thank you, a very good article, full of interesting advises. I may add i tried many times with ellagic tannins, they are effective on H2S (egg smell) only, i could never save a wine from mercaptans with tannins only. Dosage, even in white wine, from 10 to 20 g/hl of chestnut tannin (cheap and easy to clean during fining).
 

HillPeople

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I have had success with racking through a sterilized copper scrub pad suspended in the neck of the receiving carboy.
 

RPh_guy

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Thank you, a very good article, full of interesting advises. I may add i tried many times with ellagic tannins, they are effective on H2S (egg smell) only, i could never save a wine from mercaptans with tannins only. Dosage, even in white wine, from 10 to 20 g/hl of chestnut tannin (cheap and easy to clean during fining).
Thanks! I hope it's helpful.

I have to wonder whether the tannins might appear to have an effect only because oxygen is behind introduced.
I have had success with racking through a sterilized copper scrub pad suspended in the neck of the receiving carboy.
Check out the section in the article about removal. The "nuclear option" of using aeration plus an unknown amount of copper may not always be the best approach.
 

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