Unappetising food set dog off (6)
I believe the answer is:
stodge
'unappetising food' is the definition.
'stodge' can be an answer for 'food' (stodge is a kind of food). I am not certain of the 'unappetising' bit.
'set dog off' is the wordplay.
'off' indicates anagramming the letters.
'set'+'dog'='setdog'
'setdog' anagrammed gives 'STODGE'.
Can you help me to learn more?
(Other definitions for stodge that I've seen before include "Food that's hard to digest" , "treacle pudding?" , "Heavy filling food" , "Sticky stuff" , "Heavy, uninteresting food" .)