Mercaptan In The Wine; Burning Rubber ヽ(ಠ_ಠ)ノ

[Kitchen]

Hello Group,

Well I was off to figuring out a blend tonight for a tawny port and sampled all three wines only to find the dreaded burnt rubber smell and taste in each one. Needless to say I am pissed.

The three wines varietals were Petite Sirah, Malbec and Cab Sav, and I used Vintner's VR21 yeast to ferment all of them. Prior to tonight I did not detect any H2S in the wines, but it was about a month since I last checked on them. I also used this yeast to ferment these wines only, using Lalvin for all my other wines this season, and I only found this issue with these wines. So I am assuming this may be an issue with this yeast; guess I'll be sticking to Lalvin from now on.

I just spent some time racking all three, twice, and think I may be in decent shape with the Malbec and Cab Sav. However, the P. Sirah was started about a month prior to those and I fear that may be a goner at this point since the aroma/taste is so strong.

Any tips on tackling mercaptan effectively?

Thanks.

 

[stickman]

Several labs have published guide sheets for improving sulfur related issues, but the actual results achieved are always questionable. Definitely experiment before throwing the wine out, might as well learn something if nothing else.

 

[Kitchen]

Thanks for the info. I did a sniff test this morning and, although I plan on trying to save them, I don't think the P Sirah will be savable.

I am adding in fining agents to all of the wines currently, which I would prefer not to do but figure it would be best to get as much lees out as possible right now. I also have some Reduless on the way and will add it as soon as it arrives.

Here's hoping.

 

[Kitchen]

Upon further investigation into this particular yeast strain, it appears to have a very narrow fermentation temperature range of 68F to 76F. The company that produces it, unlike Lalvin, does not give any info on the H2S production, so I have to assume the worse hear given the silence on this subject. I did just read that higher then acceptable temperatures during fermentation for a yeast that is prone to sulfur issues could produce mercaptan, possibly without producing any H2S, that will only be apparent after fermentation.

I fermented these wines around 86F, and now fear the others may be lost as well.

Glad that these were not my main wines this year and only small batches. But still, it will hurt if I ultimately need to send them down the drain.

 

[blumentopferde]

I recently had an issue with Ethyl acetate. I thought my wine was lost but then I tried different fining agents and weirdly a fining agent that was actually made to reduce tannins helped really well. So I would like to encourage you to make some experiments, there's nothing much to lose!

My thread: Help! My wine smells like glue!

 

[Kitchen]

Thanks, and I saw that. I thought your wine was a goner, so we will see with mine. Although even if I do get positive results, I fear the flavor will not be what it could have been.

 

[JohnT]

it is savable with a treatment of ascorbic acid followed by a treatment of copper.

 

[Ajmassa]

That narrow 68-76° temp range is just ideal recommendations, not tolerances. But running the entire ferment cranked up at 86°—even as it’s nearing completion where it naturally wants to return to room temps— could stress any yeast, let alone a country wine strain, so a good nutrient protocol would definitely be important here. yeast selection for me is all about healthy & complete ferments. I want non-needy, high-tolerance, proven winners. Plus they say oak aged big reds lose the characteristics gained by the yeast by the time it’s ready to drink anyway. Lots of great yeast options out there, but I don’t think I’ve ever seen vr21 mentioned for big reg reds- good bad or indifferent.
I wouldn’t be so willing to dump it. Correcting mistakes/troubleshooting is probably the most beneficial aspect in gaining knowledge and committing it to memory. And if you can remove it I don’t see why any flavor would be lost. Before treating the whole batch you could pull a sample glass and stir it up with a piece of copper pipe. Would give you some insight into how the wine would respond to the reduless treatment.
Plus remember, it’s wine. And only a couple months old. Out of all the things we can do as home winemakers to improve our wines there’s still nothing that compares to the way time transforms a wine. Have had wine just mediocre at 1-2 yrs, bottled it but disregarded b/c wasn’t too great. Only to find at yr 3 or 4 it was all of a sudden fcking delicious! If you can get rid of that h2s i’d just stay the course. You may be pleasantly surprised.

 

[Kitchen]

Thanks for the advice. I did a test run with ascorbic acid and copper sulfite, and the smell cleared up pretty quickly. I treated the wines yesterday with 0.08g/gal of ascorbic acid and will add in the Reduless on Saturday.