So I'm fairly new to brewing (this was my fourth attempt) so I don't really have experience recognizing off-flavors. I recently made a darker beer and added some fruit extract (for 5 gallons I added about 3 tablespoons). The beer fermented fine, however there is a noticeable odd scent and flavor. The best way I can describe it is old rotten fruit. The beer isn't completely terrible, but it's by far the worst one so far. The extract itself smells fine by itself, but I was wondering if this off flavor definitely came from the extract, or if it could have come from another source.