Contamination Concerns

Good afternoon, everyone.

I have a slight bit of concern regarding my latest batch of brew. I brewed a 15 gallon batch of cream ale; all of which is fermenting in three separate 6.5 gallon glass carboys. I used two tubes of White Labs 080 Cream Ale Yeast. I converted one tube into a 2 liter starter which was then split and pitched into two of the carboys and pitched the other tube directly into the remaining carboy.

Fermentation began with remarkable speed in the two carboys pitched with the starter (incredible airlock activity within 3 hours), but there is a distinctive, strong rotten egg / sulfur odor coming from those two airlocks. The remaining carboy, into which I directly pitched a White Labs slurry, has a similar sulfur / rotten egg odor, but is much more subdued and I can smell a clean, fresh fermentation smell alongside it.

As far as my starter process is concerned:

I prepared the yeast starter by doing a brief boil on the stove of the two liter starter material. While the starter wort was still boiling I transfered it (while covered) to a clean room with laminar flow hood and placed the pot in an ice bath. At proper temperature I pitched the yeast into the starter and then transfered it to a magnetic stir plate for the next 36 hours. When I opened the starter to pitch it smelled clean.

I am ordinarily quite patient with regard to my brewing hobby, but am getting rather concerned that at least two of the carboys if not all three may be contaminated.

Sorry for the long winded post. Any help or insight would be much appreciated.

I just looked up WLP080 and it seems to be a hybrid of lager and ale yeast. In my experience Lager yeasts (all of them I have used) stink something awful of sulfur. So bad in fact that when I open the fermentation fridge my wife complains of the smell from two rooms away.

How do the beers taste? That is the only way to tell. It sounds like you are growing mushrooms from you equipment description, which is waaaay overkill sanitation-wise for brewing. I would not be concerned at all until you taste the beer.

Thank you for the replies, Willum and theredben.

I am not in the habit of removing the airlock at all during the first 7-10 days while the beer is in the primary (fear of contamination). So I am unable to say what it tastes like. But, judging from the greatly reduced airlock activity, fermentation is winding down and I should be able to check in the next few days.

Sulphur smells are a byproduct of many yeasts during fermentation, we even have a name for the smell, Rhino Farts. It means absolutely nothing whatsoever.

In fact with lager yeasts where it is quite common, the very point of the lagering phase is to get rid of it. It most other situation like brewing ales or apfelwein for example, it passes by in a few days.