Time for sulphur dioxide/campden funk to dissipate?

Wanted to keep a nice apple flavor with in a 5gal batch of Unicorn Blood I just made. Didn't want it to go dry and possibly chew up the delicate flavors/aroma. Stopped ferment early. Used half the recommended amount (kmeta 2.5 tabs, sorbate 1.25 tsp) waited 24 hours then racked into a fresh carboy.... sorry I can't cold crash at the moment.

Well I forgot how sensitive my nose is to sulphur. My cider smells like farts, not cool. Wife didn't even notice but I find it unacceptable. It's barely been 24 hours.... but any guess on how long the SO2 takes to dissipate? I don't want to keg it and trap all the dookie smell. Leaving it in the carboy with a chemically stalled (at about 1.017) fermentation any chance it will be scrubbed clean? Plan on sweetening with turbinado and carbing as well. Just wondering....

bump

Well, sulfite and sorbate don't stop an active fermentation. You may have stressed the yeast, which will produce a ton of sulfur aroma and flavor, but it won't kill the yeast. Maybe that's why it stinks?

Yooper said:

Well, sulfite and sorbate don't stop an active fermentation. You may have stressed the yeast, which will produce a ton of sulfur aroma and flavor, but it won't kill the yeast. Maybe that's why it stinks?

Click to expand...

You don't think that racking and adding those 2 compounds would arrest fermentation with the carboy at 65F? Man I sure figured it would.

I guess it could be stress funk.... don't know

Just pulled a sample, still smells a bit off but 50% less intense. Taste good. Thoughts on a salvage? Let it sit a bit more then carb it? If it's H2S and stressed yeast add nutrients? It's so close to being good, can't chuck it!

butterpants said:

You don't think that racking and adding those 2 compounds would arrest fermentation with the carboy at 65F? Man I sure figured it would.

I guess it could be stress funk.... don't know

Click to expand...

Nope.

Campden doesn't do anything to wine yeast- that's why winemakers use it as an antioxidant. It will stun/slow wine yeast in HUGE amounts, but the cider would have to have something like 150-200 ppm for that to happen.

Sorbate doesn't kill yeast, either- but it does inhibit yeast reproduction. That's why it works in a finished wine or cider, once it's clear. The yeast would fall out and be racked off and once the wine is clear, sorbate is added. There are still yeast present, but they can't reproduce so they don't restart fermentation.

By adding it to an active fermentation, it won't do anything much since the yeast have already reproduced and are already fermenting. There should be plenty of yeast in suspension to ferment, since the yeast's reproductive phase was long finished.

If the cider was very clear, though, and it was nearly done, it's possible that adding the sorbate would slow it enough. I have a feeling that it wasn't nearly done at 1.017, but I might very well be wrong (and I hope I am!).

The thing that most likely happened is that the yeast got stressed, and that will cause "rhino farts" types of aromas. If you could possibly get the cider cold, that would help stall the yeast enough that the sorbate could possibly be effective.

I have a feeling it was still chugging as well....

I'm thinking of adding some sanatized copper pipe pieces then kegging and trying to scrub out the farts with co2 by gas to liquid out+purge method.

butterpants said:

I'm thinking of adding some sanatized copper pipe pieces then kegging and trying to scrub out the farts with co2 by gas to liquid out+purge method.

Click to expand...

I don't think I'd do that. I'd just let it finish up, chill it, and drink it. Once it's finished, the sulfur may disipate. If not, then you can always try extraneous measures. It may not be H2S.

ok ok I'll wait her out a lil bit

It was still there in a very small quantity 2 weeks ago. I said screw it, chucked in some clean copper....smell gone in a few hours. Kegged it and the batch is delicious.

For ****s and giggles I even bottled a 12 pack when I noticed the stink bad 2.5 months ago. Well as a little experiment I tossed a 6 pack into the dishwasher and ran a cycle 1 day after bottling. Apparently the heat pasteurization worked like a charm cuz the heated ones are perfectly still yet the non-heated have about 3 volumes of CO2. Cool experiment but I kinda got lucky. I just force carbed the rest.

I just blew off the sulphur smell with co2. Worked like a charm. Good trick to keep in the back pocket and save a batch.