MLF and H2S

[docjavadude]

So I racked red wines off the gross lees. My intention is/was to introduce MLF bacteria to the juice tonight (fermentation is complete). One carboy (out of about 24) has a distinct sulfur aroma, another might have slight smell (it's hard to tell after my nose has been stuck with the rotten egg smell). The aroma is not overwhelming, but certainly present.

Should I

A) continue with MLF inoculation with 23 of the carboys and quickly sulfite the offending one, rack it a few more times in the next week and hope any H2S dissipates on its own;

B) continue with MLF inoculation with 23 of the carboys, sulfite the offending one, and treat with copper or bocksin asap;

C) continue with MLF inoculation on all of the carboys;

D) ditch MLF altogether and proceed with stabilization, clarification, and (if necessary) treatment for H2S?

Thoughts? Thanks for the help!

--Jeff

 

[ibglowin]

Need more info.
What was added upfront as far as Sulfite?
What yeast was used for the23 carboys?
Did you add nutrients along the way for all 23 carboys.

Why would you add sulfite to the offending one?

If it smells like H2S, then the yeast were not fed properly or didn't get what they needed during fermentation. More SO2 won't fix that problem.

I would splash rack the problem child to see if you can get rid of the H2S that has built up from a lack of nutrients etc.

Check your pH's and make sure they are within range and add MLB and MLB nutrients and inoculate the whole lot.

 

[Wade E]

I agree with above totally.

 

[docjavadude]

Hey Mike,

Normal fermentation procedure: Adjusted acids. Added Meta (1/4+ tsp per fermenter) to crushed fruit day before pitching yeast to kill wild yeast and MLB. Normal yeast nutrient. Yeast was RC212. Numbers were good all along. Fermentation was robust. Went slightly longer on the skins that I would have preferred (life gets in the way for us home winemakers, eh?), but juice was beautiful at pressing. Juice into carboys for secondary.

So I was a bit surprised by the sulfur aroma today. It was not strong enough to escape the carboy airlocks during secondary, but one Cab Sauv container in particular was pretty strong smelling at racking (getting it off the gross lees... again, a bit longer than I would have liked, but that life thing again...). I always use vacuum racking at pretty low pull, so there is not a huge amount of stirring, though the juice obviously does stir with the fall from bung into carboy. The offending smell (supposed H2S) is not present in every carboy.

So you recommend splashing the offender to release the H2S and proceeding with MLF? I am reluctant to wait on MLF, so this suggestion is very appealing. I just don't want to embark on MLF only to discover 6 weeks from now that the carboy of lovely Cab Sauv is irreparably damaged.

My suggestion of adding SO2 was to prevent oxidation and potential spoilage -- essentially stabilizing the offending carboy.

Thoughts?

--Jeff

 

[Wade E]

Make sure to add MLF nutrient or you could make a not so bad so far situation worse. All wines produce H2S and some more then others.

 

[ibglowin]

I would splash rack the bad one(s) to get rid of the H2S and proceed with MLF. You can always treat the wine with copper wire down the road if it continues to persist. It won't be irreparably harmed if that is the problem.

Where where the grapes from? Just curious.

Did you add nutrients in a timely fashion (1/3, 1/3, 1/3) or haphazardly? RC212 is not a bad H2S producer under normal conditions but it does need its food on a timely basis or it can become a problem child like any yeast.

 

[docjavadude]

Mike and Wade,

Thanks for the helpful suggestions. I'll breathe a bit and not worry so much about the potential H2S. It's the first time I've faced the sulfur smell, so was a bit concerned.

Grapes are from CA. Came in VERY late this year, but quality seems good. I am pretty disciplined in my winemaking, so things like yeast nutrient additions are timed pretty well. Again, part of the surprise with the sulfur. Of course part of the fun of this gig are the challenges that come along -- as long as they don't spoil the wine!

Thanks again for the "just relax, dude!" suggestions. <grin>

 

[Wade E]

I had a batch of Petite Syrah do the same thing and with only a splash racking after MLF it was completely gone.

 

[Manimal]

!

A young Cab should be able to handle considerable oxygen uptake without any problematic oxidation occurring. I would definitely not be too concerned about oxidation at this point... proceed with the splash racking!

 

[docjavadude]

Any thought about how long it might take to rid the wine of the aroma? I've splash racked (with gusto!) and stirred with a copper pipe, even did a rack back into the first carboy through the copper pipe. Aroma seemed to dissipate, but is definitely back. Any thoughts of how long I need to work the cab (other than, "until it doesn't stink anymore!" <grin>)?

 

[Rock]

Their is a product called Reduless that helped me last year.I tried splash racking and cooper and splash racking and cooper and none of it worked except reduless.

 

[docjavadude]

I've ordered reduless as well as Copper Sulphate just in case. Do I need to wait until MLF is complete to introduce the Reduless? I'm a bit paranoid about spoiling these wines, so would like to get the Reduless in there asap. Thoughts?

 

[robie]

I would read up on it or even contact the bacteria maker and ask about the wine going through mlf while having H2S. The reason I say this is H2S can evolve into something worse if left untreated. Be careful using copper Sulfate. It can be hard on your wine and possibly bad for you the drinker. Reduless should be all you need.

 

[Rock]

I've ordered reduless as well as Copper Sulphate just in case. Do I need to wait until MLF is complete to introduce the Reduless? I'm a bit paranoid about spoiling these wines, so would like to get the Reduless in there asap. Thoughts?

I would not rack your wine if it is going through mlf,so i would wait.I used it on my wine after mlf was over.I did do all the splash racking and stirring with copper before mlf.It did not help.I added as per instructions racked after 72 hours.It also says you can do another addition if needed,but i did not.This wine still sits in one of my barrels 1 year later,only racked 1 time since and taste and smells fine.