Beer? Bert is ordered to swallow it (6)
I believe the answer is:
bitter
'beer?' is the definition.
(bitter is a type of beer)
'bert is ordered to swallow it' is the wordplay.
'is ordered' is an anagram indicator.
'to swallow' is an insertion indicator.
'bert' anagrammed gives 'bter'.
'bter' enclosing 'it' is 'BITTER'.
(Other definitions for bitter that I've seen before include "Resentful about English beer?" , "Sharp-tasting or resentful" , "Acerbic" , "Unpalatable; a beer" , "Kind of British beer" .)