Hi All, Long time reader, first time poster. I've been brewing for about a year and a half now and I recently tried a Vanilla Bourbon Stout. Everything went well, I soaked the oak cubes in bourbon, dumped the bourbon and added to the fermenter after fermentation was done. Same with the vanilla, I added the concentrate from a couple beans soaked in a small amount of bourbon to the fermenter. Everything went fine, and I bottled (rather than kegged so I could age) - it came out at about 8.7%. After it carbonated I tried a couple bottles within the first month and was very happy with it. Seemed to get better and better with each on I tried. After about two months I opened one and it had a very chemically-taste. The closest thing it reminded me of was the smell of the pink urinal cakes in public bathrooms. Gross I know, but I have the nose of a blood hound and once I said that everyone else agreed. My question is - what could have happened to my beer? What sugar would've been left to even cause infection? I assumed after it was carbonated everything would be fine! All I can think is that there was a TINY amount of fermentables left that hadn't fermented yet that happened in the bottle (though I didn't have any bottle bombs or over carbonated beer at all!). I'm stumped at why everyhting tasted great and turned a couple months later. I left it in primary in my fermenting chamber for 6 weeks ( I know it's not recommended that long, but I gave it a shot and didn't notice any off flavors initially from the yeast). Any thoughts are appreciated!