About to open grape juice and the Spanish wine (8)
I believe the answer is:
muscatel
'wine' is the definition.
(muscatel is a kind of wine)
'about to open grape juice and the spanish' is the wordplay.
'about' becomes 'ca' (abbreviation for 'circa').
'to open' indicates putting letters inside (some letters create an opening in a word).
'grape juice' becomes 'must' (I've seen this in other clues).
'and' is a charade indicator (letters next to each other).
'the spanish' becomes 'el' ('the' in Spanish).
'ca' going inside 'must' is 'muscat'.
'muscat'+'el'='MUSCATEL'
(Other definitions for muscatel that I've seen before include "Flavoured wine made with calumets" , "drink" , "Type of wine - calumets (anag)" , "Sweet aromatic grape used for raisins, wine" , "Sweet grape variety" .)