Food vessel capsized (3)
I believe the answer is:
nut
'food' is the definition.
(type of food)
'vessel capsized' is the wordplay.
'vessel' becomes 'tun' (tun is a kind of vessel).
'capsized' shows that the letters should be reversed in order.
'tun' backwards is 'NUT'.
(Other definitions for nut that I've seen before include "Enthusiast (slang)" , "needing to get tight?" , "Cashew or hazel" , "Food put in crackers" , "Freak" .)