Sulpher smell where there never was one before.

I brewed the 3rd batch of my American Pale Ale (Sarah Nadda) 8 days ago. It is very much loved by all who have tasted it, and they are grumbling for a new batch. Like a moron, I then left for a 7 day camping trip. However, I live in Maine, and the room I ferment in is in my basement (it is actually my darkroom) and the temps there, this time of year, range from 64F to 67F. And the thermo I have in there showed me a low of 64 and a high of 67, while I was gone. When I got home today, my first stop was to check the fermentation. The room smelled like an egg fart. I pulled the lid on the bucket, and it looked like any normal fermentation I have ever had... But smelled even more like an egg fart. Now, I know that sometimes sulfur smell is sometimes a byproduct. But, why now? Why not with the other batches? I'll post the recipe, for reference.

2row pale malt: 7.5 lb
US Carmel 40 malt: 0.75 lb
German Dark Munich malt: 0.5 lb
German Carahell: 0.25 lb
US Carapils: 0.25lb

US Northern Brewer (pellets) 9% 1oz @ 60 min
German Perle (pellets) 8.3% 0.75oz @ 20 min
US Cascade (pellets) 6.1% 1oz @ flame out
US Cascade (whole, bagged) 7.5% 2oz, dry hopped

Whirlfloc tablet @ 15 min

Yeast: Wyeast WLP001 California Ale

Mashed @ 154F for 60 min

Any ideas? Thanks! Mike

No ideas?

WL001 does put off sulpher smells. It is normally not that strong though.

Today I developed a theory. Maybe it always does this, but because I am in and out of that room every day, I let the smells out, and they never accumulate. Solid theory. Oh... Wrong. It doesn't explain why the smell is so strong in the fermentor.

The other possibility is that because you are always in and out of the room, you get used to the smell as it slowly builds up, whereas this time you may have walked in while it was at its peak.

I wouldn't worry about it yet, let the beer keep fermenting. I've got a belgian blonde that I did last weekend that filled my ferm chamber with the absolutely worst sulphur smell I've ever experienced. I racked it to a secondary today in order to put it on strawberries, and tasted it while I was racking. Tasted pretty darn good...

did you re-use this yeast, or was it a fresh batch?

It was fresh batch of yeast.

might have been a funky batch of yeast or it got away from you fermenting. Lager it for a few weeks and see if it clears up.

What do you mean got away from me? And thanks for the advice! . I'm going to hang in with it.

Another possibility is if the fermentation wasn't as active as the last time you brewed it maybe the gas evolution was more vicious and pushed more of the sulfur out of solution? I suspect it's probably because you weren't used to the smell when you got back, like some other people mentioned (I know when I come back from a trip my house has a noticeable aroma to it).

A bit of an update. I've been letting it sit in the fermentor, and today I checked it. Looks fine, smells great! I'll be dry hopping soon, so will sample it then.
Thanks for all of the advice.

Mike

Yeast are living breathing creatures and shouldn't be expected to perform the exact same way everytime in a homebrewers life where many other variables are factors involved.

A lot of yeast strains can at times give off sulphur smells and in some styles it's expected as you probably know. You'll be fine but may need to age it in the primary a bit longer to drive out that sulphur.