Food from inn: mutter angrily (9)
I believe the answer is:
nutriment
'food' is the definition.
(I know that nutriment is a type of food)
'inn mutter angrily' is the wordplay.
'angrily' indicates an anagram (I've seen this in other clues).
'inn'+'mutter'='innmutter'
'innmutter' with letters rearranged gives 'NUTRIMENT'.
'from' acts as a link.
(Other definitions for nutriment that I've seen before include "Material providing food" , "diet" , "Nourishing food" , "It sustains" , "Sustenance, nourishment" .)