The word itself comes from medieval Latin jujuba, from Greek zizyphon, which in turn comes from Persian zayzafun, referring to a tree which produces a date-like fruit. The tree is sometimes called the Chinese date or Indian date tree. The image below shows some fresh jujube fruits.
The image below shows a box of Jujubes, the candy. The picture of the bee on the box reflects the pronunciation ju-ju-bee.