Juicer contains cold stuff (3)
I believe the answer is:
ice
'cold stuff' is the definition.
(I've seen this before)
'juicer contains' is the wordplay.
'contains' says the answer is hidden in the clue.
'ICE' is hidden within 'juicer'.
(Other definitions for ice that I've seen before include "Frozen water - diamonds" , "Diamonds (slang)" , "Cold stuff used in enticement" , "To put in a drink or slide on" , "Do cake decoration" .)