Drink helps make job rewarding (4)
I believe the answer is:
brew
'drink' is the definition.
(brew is a kind of drink)
'helps make job rewarding' is the wordplay.
'helps' indicates the answer is hidden within the clue (I've seen 'helping of' mean this (I've seen this in other clues)).
'BREW' is hidden in the letters of 'make job rewarding'.
(Other definitions for brew that I've seen before include "Ferment rather than distil" , "Infusion" , "Make beer by boiling and fermentation" , "Infuse" , "Ferment, concoct" .)