Sugar,(sucrose) does not have the same kind of bonds holding the atoms of its molecule together, as conductors have. A conductor has bonds that allow electrons to move through the conducting material. read more
When a voltage is applied to a conductor the electrons will be attracted toward the region with an opposite polarity. The electrons in a non-conductor are bond tightly in the bonds tolding the atoms together that form the molecule. That is why sucrose is not a conductor. read more
First of all, solid sucrose (pure sugar) is not a conductor. It is an insulator just as many other materials. But, the question is most often posed when it is combined with water and one finds that dissolved sucrose and dissolved salt create solutions with very different electrical properties. read more