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View Full Version : Degassing in Carboy



cabeasle
03-20-2012, 09:56 AM
I just had a batch of traditional finish up, and I think I am noticing some of the off smells people talk about on the forum. I'm not really sure how to label it, though. It definitely isn't a strong off-smell, but I do pick up something odd. This batch did stall out and had to be restarted along with a PH adjustment, so that might have something to do with it.

Since the batch is already done, and I don't have any degassing equipment, I am afraid to stir too much and accidentally oxidize the mead.

My question is: Can I rack this into a carboy, let the carboy sit a day or so, and then degass by swirling the carboy vigorously? I figure that will release lots of CO2, but there will be no danger of letting oxygen in because the combination of CO2 and airlock will keep oxygen from being introduced to the environment. Is that accurate, or will I be oxygenating the mead the whole time?

The mead tastes fine, but the smell is certainly off putting and it would be nice for it to go away :)

wayneb
03-20-2012, 10:41 AM
You can indeed. In fact if the smell is really objectionable and if you think it may be caused by sulphur compounds (hydrogen sulphide, various mercaptans, etc.) it is best to try to get that stuff out of your mead right away. It is even worth a risk of oxidation - although since meads are more resistant to oxidation damage than grape wines, you're probably even OK if you want to "spash rack" a bit - that is racking with the outlet of your racking tube up above the liquid level in the destination carboy to allow trapped H2S out as the liquid splashes onto the surface. If after the splash rack you still smell foul things, you can try a simple copper treatment - swirling a clean, bare copper wire (or a completely clean pre-1982 penny) in the mead to see if that fixes the problem. There is a complex series of reactions that takes place when H2S is present in any alcoholic solution, and the longer you wait to get that sulphide out, the more stable and stubborn to remove it becomes. BTW - don't try the copper trick until you are sure that fermentation is over, since copper in your must while the yeast are still active is actually a yeast stressor, which can make the remaining active yeast produce even more H2S!