Pork Floater

At a barbque you're offered a sample of someone else's hip microbrew beer and you leave behind a bit of your bbq meat in their drink. Unexpected meaty backwash. Or any case of leaving some pre-chewed bits of food in someone else's beverage after sampling.

"You gotta try this one."

"Wait a sec, let me finish this, don't want to leave you a pork floater."