I set up my camera on a tripod and got my angles, lighting and background sorted before taking a snap of the mandarin unpeeled. I then removed the mandarin, peeled it and placed it back exactly where it was and facing the same way. I needed to take a phone snap for reference here. I took another photo of the orange fully peeled then removed it again and placed the peels around the same spot and took a third pic.
I imported the 3 photos into Photoshop as well as an image of the earth with political/country outlines and layered them on top of one another and made any adjustments necessary to align them precisely. I made a selection of the map layer (minus oceans) and applied that selection to the peeled layer, inversed it and cut it out. That left me with an orange peel map. Next I erased the fully peeled orange layer and carefully masked out all but the scattered peels to leave the composition more or less complete.
Final steps involved touching up with some shadows and highlights as well as painting on some yellow tones to the orange map as well as adding filter and levels adjustment layers.