Inquiry as it is no vintage brew (13)
I believe the answer is:
investigation
'inquiry' is the definition.
(investigation is a kind of inquiry)
'it is no vintage brew' is the wordplay.
'brew' indicates an anagram.
'it'+'is'+'no'+'vintage'='itisnovintage'
'itisnovintage' with letters rearranged gives 'INVESTIGATION'.
'as' acts as a link.
(Other definitions for investigation that I've seen before include "Probe" , "Inquiry" , "fact-finding search" , "Examination" , "Analysis" .)