H2S in my hydromels, what am I doing wrong??

[Yuri]

Hi everyone,

This is the second time I have tried to make a flower tea hydromel that resulted in sulfur smell and I really can't see what is so different about my recipe than what is shown on the internet. The first time I used less nutrients and staggered them, I read that I should add more nutrients and front-load. I also read that adding sulfites for sanitisation can add a risk of sulfur reduction (chemical reduction), so I decided to wait 36 hours in stead of 24 hours before adding my tea to the must to allow it to dissipate. So here is what I did:

475 grams of honey in about 4.75L of water (which was part tea and mostly elderflower tea steeped for 36 hours outside the fridge with 1 campden tablet). Half a packet of CY17 wine yeast. Front loaded a little over 5 grams of Fermaid O (which is a lot in my opinion). SG was 1.038. 3 days later I feel like I am starting to smell sulfur again.

I have some pure copper wire, but the danger of copper sulfide/sulfate has me not even wanting to try that for a solution. I am more just wondering how I could have possibly prevented this? Maybe someone has a theory..

Yuri

 

[HeartOfGold]

If you think that sulfur smell is an issue, then fermenting temp must be low, but I think your hydromel don't have an issue. Adding Sulfitet is not an issue with commedical yeasts.

 

[An Ankoù]

Only a shot in the dark, but try changing your yeast. CY17 is, I think, one which produces the enzyme beta glucosidase which changes the flavours of certain aromatics. It is paticularly used to get the floral scent and taste when using sauvignon blanc grapes. While I can't imagine what biotransformations might take place in your honey/tisane mix, let alone where sulphur smells are coming from, there's certainly something going on. MJ do a specific yeast for mead, M-5. I'm using it for the first time and it looks very promising. Failing that, you might try a champagne or cider yeast.
Good luck.

Could you give us a link to your Internet recipe, please.

 

[MashBag]

For me h2s is a yeast stress marker. So either it doesn't have enough yeast available nutrient (yeast starving) or the Campden tablet is nailing then (yeast dying).

The latter is my favorite.

 

[An Ankoù]

For me h2s is a yeast stress marker. So either it doesn't have enough yeast available nutrient (yeast starving) or the Campden tablet is nailing then (yeast dying).

The latter is my favorite.

Why do you even need a Campden tablet? I've never, ever put one in my wine musts or meads.
I might put a tiny sprinkling of metabisuphite in a bag of freshly picked raspberries that I'm going to freeze for a later addition to beer. But that's it.
All this rampant lobbying from SO2 pressure groups has really got to stop!

 

[Yuri]

Only a shot in the dark, but try changing your yeast. CY17 is, I think, one which produces the enzyme beta glucosidase which changes the flavours of certain aromatics. It is paticularly used to get the floral scent and taste when using sauvignon blanc grapes. While I can't imagine what biotransformations might take place in your honey/tisane mix, let alone where sulphur smells are coming from, there's certainly something going on. MJ do a specific yeast for mead, M-5. I'm using it for the first time and it looks very promising. Failing that, you might try a champagne or cider yeast.
Good luck.

Could you give us a link to your Internet recipe, please.

I use MJ's yeast almost exclusively and I have never had issues with funky flavours using them for mead. I have tried M05 now for the first time but it is not done fermenting. The reason I picked CY17 actually, is because MJ recommend it for elderflower wine, so just changing the sugar source to honey seemed like the same ballpark to me. I remember reading that CY17 actually won some competitions making elderflower meads. I feel like the sulfur smell is gone, but I definitely wouldn't say it smells "good". Maybe it will age out? I am not really following one recipe in particular, just a collection of many that are found on youtube etc.

Thanks for the suggestions though, I didn't know beta glucosidase had such an effect, I will look into that. I only know it from enzyme assays .

 

[Yuri]

If you think that sulfur smell is an issue, then fermenting temp must be low, but I think your hydromel don't have an issue. Adding Sulfitet is not an issue with commedical yeasts.

The temp range of CY17 is 16-24C and my house was at a pretty steady 20C while fermenting. Thanks for the tip on sulfites though..

 

[Yuri]

For me h2s is a yeast stress marker. So either it doesn't have enough yeast available nutrient (yeast starving) or the Campden tablet is nailing then (yeast dying).

The latter is my favorite.

Is 36 hours not enough to get the excess sulfites out?

 

[Yuri]

Why do you even need a Campden tablet? I've never, ever put one in my wine musts or meads.
I might put a tiny sprinkling of metabisuphite in a bag of freshly picked raspberries that I'm going to freeze for a later addition to beer. But that's it.
All this rampant lobbying from SO2 pressure groups has really got to stop!

I don't actually use tablets, I have a bag of metabisulphite but metabisulphite is the only component of Campden tablets, they are the same just a different name. I add it to sanitise the dried flowers, I buy them from a tea shop and I really want to make sure even the spore-forming bacteria are dead as 100C water will not kill them.

 

[MashBag]

Is 36 hours not enough to get the excess sulfites out?

No. Not necessarily, and most likely no in this case. Sulphur stays 'in' the liquid until required. This is precisely why it is added to wine.

It doesn't dissipate or blow off.

This recipe really would be better without it.

 

[MashBag]

metabisulphite

Which metabisulphite. Sodium or potassium? Camden tablets come in both forms.

 

[MashBag]

I don't actually use tablets, I have a bag of metabisulphite but metabisulphite is the only component of Campden tablets, they are the same just a different name. I add it to sanitise the dried flowers, I buy them from a tea shop and I really want to make sure even the spore-forming bacteria are dead as 100C water will not kill them.

Dried.. Typically does not harbour bacteria (nothing to feed on)

Better pop them in a little later, once the ferment is established and the yeast will most likely clean up for you.

 

[An Ankoù]

I don't actually use tablets, I have a bag of metabisulphite but metabisulphite is the only component of Campden tablets, they are the same just a different name. I add it to sanitise the dried flowers, I buy them from a tea shop and I really want to make sure even the spore-forming bacteria are dead as 100C water will not kill them.

I'm not sure that MBS is as universally efficacious as you might think. I've read, somewhere, that it isn't particularly useful for inhibiting gram negative bacteria. Just been trying to find the reference again, but haven't got there yet.
Anyway, I'd still leave it out of my recipe. It's not as if your herbalist is likely to be infested with anthrax.

 

[Yuri]

Dried.. Typically does not harbour bacteria (nothing to feed on)

Better pop them in a little later, once the ferment is established and the yeast will most likely clean up for you.

I'm gonna go reply to both those comments in one go. Trust a microbiologist here when I say potassium or sodium makes no difference when the concentration is so incredibly low and yes, there are viable dormant bacteria on those flowers. They don't need anything to feed on at the moment. Without a doubt the 100C will kill almost all bacteria, but then elderflower requires 24 hours of steeping. Since this is a hydromel (low ABV) I really don't want to take any chances getting something in there.. but that may just be my diligence. Perhaps I will try to add some sanitised dried flowers later though as you suggested.. Do you have any idea what amount of flowers is good when they will be in there for like a month?

 

[Yuri]

I'm not sure that MBS is as universally efficacious as you might think. I've read, somewhere, that it isn't particularly useful for inhibiting gram negative bacteria. Just been trying to find the reference again, but haven't got there yet.
Anyway, I'd still leave it out of my recipe. It's not as if your herbalist is likely to be infested with anthrax.

You're right, sulfites aren't the end all be all, but none at all? I suppose gram negative is what I was afraid of. Environmental bacteria might rarely infect people, but the compounds they make especially from sugar carbon sources can be pretty nasty. Butyric acid