Bags containing new crisps, perhaps (6)
I believe the answer is:
snacks
'crisps perhaps' is the definition.
'bags containing new' is the wordplay.
'bags' becomes 'sacks' (sack is a kind of bag**).
'containing' indicates putting letters inside.
'new' becomes 'n'.
'sacks' enclosing 'n' is 'SNACKS'.
(Other definitions for snacks that I've seen before include "Light bites such as crisps" , "Small food amounts between main meals" , "Nibbles" , "Small or casual meals, often hurried" , "Light informal meals" .)