Fermentation smells like rotten eggs

I recently brewed a batch of IPA and pitched a yeast starter of harvested White Labs WLP001 (California Ale Yeast Blend). While the yeast was being pitched, I noticed it didn’t smell quite right. In fact, it smelled awful, like rotten eggs. I felt like a kid finding out about Santa Claus – quite disappointed. By the time I got a whiff, it was already too late. It was already dumped into the primary. I have a brew day tradition of letting my wife add the yeast to the sweet wort. As she was pouring it in, she kind of made an unpleasant face (like when someone in the room farts).

Fermentation started up quickly – about 4 hours later. I kept an eye on things closely and kept sniffing the C02 coming out of the air lock. Yep… it stunk. Did I ruin my beer? Will the smell fade? Even if the smell fades, is it ok to drink? These are a few of the questions that went through my head as I went into research mode. I visited a few hundred websites and the general consensus was that I either had an infection, or the temperature was too high. Either scenario would produce the nitrogen sulfide byproduct from fermentation. If it’s an infection, the horrible sulfur smell would stick around in the finished beer. If it was just a temperature problem, then the smell should fade after a couple of weeks of aging. We will see…

July 15, 2014 – Here we are a few weeks later. I just cracked open the airlock, took a whiff and couldn’t detect anything. I actually can’t believe it. I did move the beer off of the primary fermentor about 2 weeks ago and let it sit in the secondary. I can tell the beer is finished because there hasn’t been any activity in the airlock at all. I watched it for a good 5 minutes and the air wasn’t moving at all. This is a pleasant surprise. I definitely don’t want to drink infected beer. I know it’s not harmful, but it’s just not enjoyable when you have an off-flavor/aroma like that. I plan on dry-hopping this batch with an ounce of citra for 4 days before kegging. I’ll append a tasting note with the final results.

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