To get a nice reflection you'll want to add
Materials, especially glossy or refractive materials, are hugely dependent on the surrounding light sources. Try adding a nice big mesh light (or area lamp) for the material to reflect
Light tends to reflect off of materials more at glancing angles, and reflect less when hitting a surface straight on. If you look at your top-down reference picture/texture, there is hardly any visible specular reflection ("specular" refers to perfect or mirror-like reflections, such as the sharp white highlights)
To simulate this, add a Fresnel node, plug your bump/normal map into it, and connect it to the Mix factor of the mix node which is mixing in your glossy shader.
This will make a big difference, especially on surfaces with lots of small variations in angle.
In this example I slightly complicated things by giving the rind a lower IOR than the rest. A more simple setup could just connect one of the fresnel nodes straight to the mix shader (both selected). However given that the rind and fruity parts of the orange have quite different optical properties, you probably do want to simulate that in some way.
Note that an actual orange is quite complex, with the fruity parts being translucent with a visible internal structure. To properly simulate one, you might want to model the slices and rind separately and use a translucency, SSS or volume shader (somewhat similarly to this).