Sample of Muscat chardonnay in bag (5)
I believe the answer is:
catch
'bag' is the definition.
('catch' can be a synonym of 'bag')
'sample of muscat chardonnay in' is the wordplay.
'sample of' indicates the answer is hidden within the clue (I've seen this in other clues).
'CATCH' is hidden in the letters of 'muscat chardonnay in'.
(Other definitions for catch that I've seen before include "Hear < hit" , "Grab in mid-air" , "Grasp - overtake - overhear - surprise" , "Dismiss (batsman); break (in voice)" , "It's taken by a fielder to dismiss a player in baseball and cricket" .)