The orange is there to add moisture (from the juice) and a complementary flavor to the apricot (from the zest and juice). However, if you don't like orange juice, you can add a different type of juice, like apple. Or, you can even just add in an equal amount of water instead. Finally, to replace the flavor from the zest, you can try lemon zest instead. Or, just leave it out, and the bliss balls will still taste great!