Hydrogen sulphide - major frustration- what am I doing wrong

[CalicoCellars]

Hey folks; am facing some H2S issues even with Sensy yeast; which is supposed to be a low sulfide yeast. This is in 10 gallons Sauvignon blanc juice. Didn’t get the chance to get YAN measurements but maybe the juice didn’t have additional nutrients

Is there a risk of adding too much yeast nutrient? Is there a threshold? I have heard that the main thing to worry about is potential for microbial spoilage during aging but I am intending the white will only be for 2 years tops and sulfite can also control this, right?

Thanks in advance for any guidance

 

[Ohio Bob]

Hey folks; am facing some H2S issues even with Sensy yeast; which is supposed to be a low sulfide yeast. This is in 10 gallons Sauvignon blanc juice. Didn’t get the chance to get YAN measurements but maybe the juice didn’t have additional nutrients

Is there a risk of adding too much yeast nutrient? Is there a threshold? I have heard that the main thing to worry about is potential for microbial spoilage during aging but I am intending the white will only be for 2 years tops and sulfite can also control this, right?

Thanks in advance for any guidance

Is this from a juice bucket? I would assume the YAN would be close, as the SG and pH are usually pretty good.

Did you ferment in an open bucket, where the yeast has access to lots of oxygen? Yeast can be stressed by not getting enough oxygen.

 

[winemaker81]

Hey folks; am facing some H2S issues even with Sensy yeast; which is supposed to be a low sulfide yeast. This is in 10 gallons Sauvignon blanc juice. Didn’t get the chance to get YAN measurements but maybe the juice didn’t have additional nutrients

Is there a risk of adding too much yeast nutrient? Is there a threshold? I have heard that the main thing to worry about is potential for microbial spoilage during aging but I am intending the white will only be for 2 years tops and sulfite can also control this, right?

Thanks in advance for any guidance

Folks speak of thresholds for too much nutrient, but I can't recall any hard figures.

I go by package direction on the nutrient, and if a strain has high needs, I add 50% more.

At this point you have H2S, so you need to act immediately. The longer it's present, the worse it gets. Add a 25% to 50% dose, a dose of K-meta, and stir the heck out of it. Do this in a well ventilated area and run a fan -- the reek gets worse as you stir to release it from the wine.

Following are my notes from a 2020 second run wine, which had bad H2S. I had to go as far as adding Reduless to it. I've had it twice since then, but caught it early enough that K-meta and stirring addressed it. Since then I'm paranoid about H2S and ensure I have sufficient nutrient added.

https://wine.bkfazekas.com/2020-red-blend-second-run/