Malodorous Fermentation

[kgaugler]

My latest batch of my Anchor Steam clone has a weird odor coming from the airlock. It is kind of sulfury. I've made this style of beer several times in the past and haven't noticed this odor before. I use Wyeast #2112 California Common yeast with a fermentation temperature of 62F. I am afraid that I have some kind of contamination (bacteria?) but am not sure. Anyone ever experienced this before. Should I even wait for the primary to finish????:(

[Jughead]

Yes, wait and see. Sulfur smells are normal.

[Stodbrew]

A lot of yeast, especially lager yeast, throw off a sulphur aroma during fermentation. It should be scavenged off by the end of frementaion. Let the primary finish, and give it a smell and taste at the end and then see what happens.

[kgaugler]

Thanks for your help. Funny I've never noticed it before.

[YamahaXS]

I have heard that smell/taste can be a sign of stressed yeast.

[barley ben]

I agree with Stod. I have heard that is a common smell when using lager yeast and it's supposed to get cleaned back up at the end of the fermentation. I'm using a White Labs San Fran Lager yeast right now and have the same odor coming out of my air lock.

[kgaugler]

As an update... it is now day 6 of fermentation and the smell seems to have gone away. I will most likely be racking to secondary tomorrow.

Once again, thanks for the help.

[paul84043]

You will also notice this smell when making a Hefe, or wheat based beers. I have had a few do the same thing and it has always worked out in the end. It's got something to do with the type of fermentables in the wort.
No worries. It's perfectly normal.