Felt differently concerning small amounts of surplus food (9)
I believe the answer is:
leftovers
'amounts of surplus food' is the definition.
'felt differently concerning small' is the wordplay.
'differently' indicates an anagram.
'concerning' becomes 'over' (I've seen this before**).
'small' becomes 's' (abbreviation - e.g. clothes size).
'felt' anagrammed gives 'left'.
'left'+'over'+'s'='LEFTOVERS'
(Other definitions for leftovers that I've seen before include "Remains" , "survivors" , "Uneaten scraps" .)