Revolutionary brew of beer by a beginner (5)
I believe the answer is:
rebel
'revolutionary' is the definition.
(rebel is a kind of revolutionary)
'brew of beer by a beginner' is the wordplay.
'brew of' indicates an anagram (I've seen this in other clues).
'by' says to put letters next to each other.
'a beginner' becomes 'l'.
'beer' is an anagram of 'rebe'.
'rebe'+'l'='REBEL'
(Other definitions for rebel that I've seen before include "One who rises up" , "Refuse orders" , "Oppose authority" , "Insurgent, mutineer" , "One who opposes the powerful" .)