Sweet wine, unfortunately stuff on the turn (7)
I believe the answer is:
marsala
'sweet wine' is the definition.
(I've seen this before)
'unfortunately stuff on the turn' is the wordplay.
'unfortunately' becomes 'alas' ('alas' is used to express regret).
'stuff' becomes 'ram' (ram can mean to stuff or push).
'on the turn' says the letters should be written in reverse.
'alas'+'ram'='alasram'
'alasram' backwards is 'MARSALA'.
(Other definitions for marsala that I've seen before include "Fortified wine from Sicily" , "Sweet Sicilian wine" , "Fortified Sicilian wine" , "Wine - as alarm (anag)" , "Sicilian dessert wine" .)