Rotten egg smell from primary fermentation

[Braden]

Doing a Cabernet Sauvignon Eclipse Kit right now. There is a smell of rotten eggs a little bit out of the air lock. I looked it up and there’s a few reasons as to why. I fermented around mid to uppers 70s and it’s currently sitting at 72-74 right now and slowing down on the activity. I saw temps between 75-80 could produce more sulfur and give you that smell but I thought red wines benefited from a higher fermentation temp. What could I do to fix it? Just a few racks once it’s finished up fermenting?

 

[crabjoe]

For me, adding yeast nutrients and stirring fixed my problem.

I say splash rack it and make sure to give the yeast some nutrients.

 

[cmason1957]

The answer depends on the current sg you have. If you are below about 1.050 adding yeast nutrient won't help the yeast. Splash racking may help.

As to higher temps, for kits, I don't think higher than the 70 or so they say to ferment at is a good idea. Kits aren't the same as having all those grape skins and such in your must. I actually prefer to do my kits at a lower temp around 62 or so and let it take a little bit longer.

 

[dralarms]

Stressed yeast. Only a few things that’ll fix it. If fermentation has not finished the add some nutrients. If it has finished then racking through some sanitized copper might be the only way to save it.

 

[cmason1957]

If it is stressed yeast, please do not just rack through copper. Yes, copper is the solution, but racking through copper puts an unknown amount of copper into your wine. Consider using Reduless or do the testing to determine the minimum amount of copper sulfate to add to solve the problem.