Was the only way for him to be sure, and to be sure it was the same source as well. There was that same subtle aftertaste that made his nose wrinkle a bit. "If it's one, it could be everything edible at the stall- I'd half worry about it bein anything touched, too." A growl to his voice, ears pinned back and tail curled close to a leg.

Hopefully it was just whatever was edible and not objects that would be touched often, or could prick skin- "Probably is an ass."