is my beer 'green' or is my aftertaste from too-high temps during fermentation?

I just tried a bottle of a peach IPA that had been bottle conditioning for 3 weeks. It has a strong alcoholic aftertaste which I am guessing is the fusel taste? The yeast I used is "SAFALE US-05 DRY AMERICAN ALE YEAST" I'm not sure if just needs to condition a little longer, or if it is from too-high fermentation temps. I've brewed 4 batches before, and never had to worry about it being too warm because I lived in a basement apartment and it was always cool... but now I'm up on the fourth floor and while the apartment is generally around 73 degrees, it may have gotten up above 75 from time to time during the fermentation. i'm not sure what a 'green' beer tastes like, or what it tastes like if the beer is not finished bottle conditioning yet, so I 'm not sure if that is all the taste is. It's well carbonated, and tastes delicious except for the burny afteraste.

Thanks!
M

Yep, sounds like the classic description of fusel alcohols resulting from too-high fermentation temperatures. Unfortunately, it's too late for this batch, but the prescription for future batches is to pick up a plastic "rope tub" (usually for laundry) from the department store (maybe $7-$10) and set the carboy in a water bath, possibly with some frozen juice/pop bottles to get those temperatures down next time.

Too high temps.

They might mellow out a little with time though.

I second the high temps; 75º ambient means your beer was likely over 80º during peak fermentation. That's warm enough to create a number of off flavors including the hot alcohol you describe.

Young beers often have green apple and other odd fruit flavors. Letting your beer sit a little longer on the yeast cake can help with fusel alcohols and other hot solvent, green and "off" flavors from young beer. Basically, you give the finished beer what's commonly known as a diacetyl rest. That is, the beer sits for an extra week in the primary fermenter so that yeasts can consume and transform earlier alcohol precursors and fusels into more pleasant esters. So, after your beers are finished fermenting (through the use of consecutive gravity readings), there's no harm and all the benefit in the world from letting it sit for an extra week on the yeast cake in the primary.

aiptasia said:

Young beers often have green apple and other odd fruit flavors. Letting your beer sit a little longer on the yeast cake can help with fusel alcohols and other hot solvent, green and "off" flavors from young beer. Basically, you give the finished beer what's commonly known as a diacetyl rest. That is, the beer sits for an extra week in the primary fermenter so that yeasts can consume and transform earlier alcohol precursors and fusels into more pleasant esters. So, after your beers are finished fermenting (through the use of consecutive gravity readings), there's no harm and all the benefit in the world from letting it sit for an extra week on the yeast cake in the primary.

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Ok ok, first off, conditioning time will not eliminate fusel alcohol. Or solvent-y flavors. Second off, a diacetyl rest cannot be done in a "finished" beer, it needs to be done in a beer where the yeast is still active. It's commonly done about 75-85% of the way through fermentation.

I agree that time on the cake after FG can help smooth a beer out to some extent, but your advice is pretty misleading.