Experienced winemakers - help me figure this out?

So, it’s been a challenge from day one this harvest. I’m hoping the more experienced winemakers can help me out with this one. Here’s the problem:

I put wine into a few barrels that had been newly sulfur wicked but unfortunately without rinsing them with water first. My screw-up. Wine smelled like matchsticks. Everyone keeps telling me that I need to copper sulphate treat it, but I’m a little reluctant to jump into doing that until I’ve eliminated everything else, as it is a poison after all. Wine does not smell of hydrogen sulfide (H2S), i.e. rotten eggs. It only smells like matchsticks, which would suggest it’s just over-sulfured. As far as my knowledge goes, that would seem to indicate that it does not contain mercaptans, which is what the copper sulfide would treat. So my question is:

  1. Have you ever had matchstick smell that was actually mercaptans or hydrogen sulfide?
  2. Most sulfur will vent out over time, or can be aerated out, but have you had a barrel that would not integrate the sulfur?

I’m waiting on the lab reports, but there’s a lag there, so thought I’d ask the experienced winemakers here. Thank you for any advice you might have. flirtysmile

Just stir it with a copper pipe if you don’t want to add blue powder.

What kind of wine is in there?

That’s a cool tip, Todd. It’s Zin.

Grab a glass and a thief, stir in increments of 15 seconds and taste.

It would be helpful to measure the SO2 level. Matchstick seems more like SO2 than H2S, which is an eggy odor. If the SO2 is the culprit not sure that copper will help.

FWIW I treated a reduction problem Syrah in the past with CuSO4 and had good results, using bench trials first to find the smallest amount that worked. A lab test of the treated wine shows less copper than permitted in the local drinking water.

Is it an old barrel? It might just be barrel funk, although if it is a new wine it might not have had a chance to pick that up.
I’d splash rack first just to see if that helps.

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Thanks all.

Stuff back from lab, no funky stuff in there. It’s got high pH. Total SO2 also getting up there at 52mg/L and free was only 3mg/L and it hasn’t gone through malo yet. I’ve splash racked it already, but will try to do so again. It helped, less odor now. Lab thinks the pH might be contributing to the matchstick, somehow.

I’ve filled recently SO2 gassed or sulfur wicked barrels without rinsing before. The sulfur impact has always been temporary, and hasn’t inhibited malolactic. It smells and seems scarier than it is in the long run. I hope this is your experience too.

What’s the pH?

that’s a rather high TSO2 post primary. How much did you at at crush?

My notes say 66ppm, but I don’t think that’s correct note as I remember agonizing over a potential miscalculation the night after, only to come to the conclusion I’d done it right. I never really do more than 25-30ppm if fruit is pristine (or 50ppm if fruit is a little less pristine), but it’s possible I went as far as 66ppm. This was first harvest of the year, mid Aug kickoff already. And I was frazzled and scrambling to get things in line that early, so not impossible miscalculations took place.

Never do math or additions at night during harvest. It can wait.

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How did the wine turn out? Were you able to blow off the match stick aromas? With the higher TSO2, did you get it through ML? Not sure if you’re going native ML but Alpha works really well with higher TSO2 levels. I’ve definitely had a couple wines in the past with an odd match aroma, which I likened to toasted yeast, with no chemical signatures toward H2S; I ran everything I could at ETS. The only conclusion I came to was both ferments may have struggled due to excess fining or cleanliness in the juice up front. They were slow and steady throughout and took a long time to wrap up once they were below 1Bx. One was hit too hard with fining agents (for sparkling) and the other was a lees filtered wine without enough solids added back for ferment.

While both of mine were whites, both ended up with those aromas toward the end of ferment. Like yours, no lab analysis pointed to a sulfide or sulphur issue. The aroma all but dissipated as they aged for a few months post ferment, never to come back. TSO2 was a non factor for both wines.

It’s turning out fine, thanks. Glad I didn’t go down the copper sulfite route and chasing what most likely would have been the wrong thing. There’s a hint of reduction still in wine, but those offending matchstick notes are almost completely gone. It just needed some time and air in tank. I’m racking it today, actually. I don’t normally rack my reds until before bottling, but this one can probably do with coming off lees.

You never did mention what the pH is of the wine - both pre and now probably post ML. Please provide.

Also, you made a statement in your original post which I believe is incorrect - copper sulfate does NOT treat mercaptans on its own. It treats H2S issues. The only way to ‘treat’ mercaptans is to hyper-oxidize first with Ascorbic Acid because mercaptans are di-sulfides and need to be ‘broken apart’. Then you can hit it with Copper Sulfate to take care of H2S. Had to do this once when working with another winery on a riesling - it made the wine ‘drinkable’ but screwed up the aromatics in my opinion.


The best advice I ever received from another winemaker regarding any problem was this: “Wait.”
Oftentimes the issue will resolve itself.
Sometimes it remains and you have a better understanding
Infrequently (though this is the dangerous route) the problem is worse.