Sulfer and Yeast

[TarheelBrew13]

I have been working on a Belgian Wit recipe for some time and am having trouble with the finished beer smelling like rotten eggs. I know this is because of sulfur compounds produced during yeast replication but I'm unsure how to fix it.

At first I thought this was just because of the yeast I am using, WLP400. So, I tried WLP001, WLP320, and WLP380. After these three batches the 001 produced a strong sulfur smell, the 320 produced a moderate sulfur smell and the 380 produced none.

Anyone have any thoughts as to why I may be getting so much sulfur in the beer. Even after bottle conditioning for 3 weeks the beer smells terrible when opened (but tastes amazing). I am oxygenating all my wort before pitching yeast for 60 seconds with pure oxygen and a .5 micron stone. My ambient fermentation temp is about 68-70 degrees (don't have a way to ferment cooler right now).

I seem to be getting slightly lower levels of sulfur when I overpitch but I'm not sure that this is the reason. There must be a way to get the smell of rotten eggs out of my witbier.

 

[eastoak]

how long are you letting sit in the fermentor? i expect sulfur smells from some yeasts but the smell always goes away after fermentation and bottle conditioning.

 

[TarheelBrew13]

I have made several batches but all have stayed in the fermentor for at least 3 weeks and some as long as 6 weeks. All the bottle conditioning has been for at least 2 weeks.

 

[Grumpybumpy]

I think malnutritioned yeast will release sulfur smells but it should go away. It could also be just a character of that yeast. I'd be interested to know if you'd have a different result if you gave them some nutrients at the beginning

 

[wailingguitar]

Usually time in fermenter will deal with sulfur. If you keg, you can scrub it out with CO2... obviously neither of those will help the bottles. Time should deal with it though as the yeast cleans up after itself in the bottled beer.

 

[cricky101]

I've got the same thing happening with a Belgian wit and wlp400 right now. Fermenter for 3.5 weeks, hit the numbers just fine, and been in the keg for 3 weeks. It smells horrible like rotten eggs.

The taste is good, but I can't get past the sulfur aroma.

 

[TarheelBrew13]

I've been doing some reading on the production of Hydrogen Sulfide (the chemical causing the rotten egg smell) and it looks like this is produced when yeast replicates. Specifically, when there is a lack of nutrients in the wort. I've been making a traditional Witbier with 50% pale malt and 50% unmalted wheat. I wonder if this is the cause of my extremely high levels of H2S.

I'm considering two possible solutions. First, opening a few of my rotten egg beers, putting them in a growler and forcing CO2 in the growler through a .5 micron stone. From what I've read, H2S is a very volatile compound and is easily reduced by this technique. Then I can re-carbonate the beer and see if the aroma is gone.

Second, I'm thinking of brewing a new batch and adding some yeast nutrient to the wort. Perhaps this will reduce the amount of H2S produced and make my beer smell nice.

Anyone have any thoughts?

 

[Grumpybumpy]

Do both! Like I said before, I'd be very interested to see if the nutrients take care of the problem. Keep us posted