IPA woes

[LawDawg05023]

2nd time brewing this recipe, loved it. Decided to brew it again, only this time there is a "sour" smell coming out of the fermenter. You can still smell the hops but there is a sour undertone to it. Did everything the same as the last time, except the mash temp was higher. 165 instead of 149. Question did the higher temp contribute to the sour smell, and will it settle out?

[slothrob]

I suppose the yeast could be a little more stressed by all the unfermentable sugars in the new beer, making a different set of esters. Or maybe there is another variable, like temperature or yeast age or health that is resulting in a difference in the fermentation.

However, I wouldn't worry too much about weird smells coming from the fermentor. Someone said to me once that whatever odd smell comes out of the fermentor is another odd smell that won't end up in your beer, which I've found to be often true. Some yeasts smell awful during fermentation and taste delicious.

165°F is a very high mash temperature. Did you mean 155°F? I'd be curious to know how well a beer mashed at 165°F ferments out. I'd expect a high FG.

[LawDawg05023]

Thanks for advice, can't tell you how much you have helped me in the past

[slothrob]

I'm glad I've helped.

What yeast are you using? For example, American Ale and American Ale II yeasts are popular for American Pale Ales. The first usually doesn't generate much of an odor from the fermentor, but the latter can really stink toward the end of fermentation, I've found. American Ale II yeast can be very tasty, though.