Fruit pulp, zest only, in long drink (9)
I believe the answer is:
pineapple
'fruit' is the definition.
(pineapple is a kind of fruit)
'pulp zest only in long drink' is the wordplay.
'pulp zest only' becomes 'pp' (I can't justify this - if you can you should believe this answer much more).
'in' indicates putting letters inside.
'long' becomes 'pine' (to pine for someone is to long for them).
'drink' becomes 'ale' (ale is a kind of drink).
'pine'+'ale'='pineale'
'pp' put into 'pineale' is 'PINEAPPLE'.
Can you help me to learn more?
(Other definitions for pineapple that I've seen before include "Large fleshy fruit with a tuft of stiff leaves" , "that might go off?" , "bomb" , "Fruit grown on ground" , "Fruit (tree and fruit!)" .)