Division of supermarket is into drink (5)
I believe the answer is:
aisle
'division of supermarket' is the definition.
(supermarkets are arranged in aisles)
'is into drink' is the wordplay.
'into' is an insertion indicator.
'drink' becomes 'ale' (type of beer).
'is' put inside 'ale' is 'AISLE'.
(Other definitions for aisle that I've seen before include "Passageway between pews" , "that would-be bride hopes to make it up!" , "Church walkway" , "way to the altar?" , "Division of the nave in church" .)