Not sure where to ask this question but here goes.
I normally PM but did an extract/steep amber ale since I wanted to get a batch done quick.
All went well. 2 weeks primary 2 weeks secondary, keg and let sit about a week on 12psi with a sample here and there. When the fierce hop bite subsided I thought it tasted pretty good and called it done. Using my brand new beer gun I bottled a six pack and took to the in-laws for thanksgiving. It went over well and one brother-in-law who home-brews too drank 3 to himself so I knew it was good. I bottled another six pack for a future card game at a friends house, since I knew the keg wouldn't last. And it didn't
2 weeks later (this last weekend) at the card game. My bottled beer had a total butterscotch taste and smell. (overwhelming IMO) My buddies didn't know any better but I was royally dissapointed.
My question is why the huge difference in taste? If my beer had alot of diacetyl wouldn't I have noticed it earlier? I used dry yeast and temps were good. Did I not clean the beer gun well enough and introduce an infection?