My friends always asked me why sometimes they could shoot some nice food photos with their smartphone, but sometimes crapped.
The answer is the difference between ammatuer and professional, by luck vs by manipulating.
As a professional photograper, basically, we have experience and solid foundation of photography, fully controlling the lighting and the camera setting for the best result.
But more important than that are the special skills and technique for good food photography: food styling, shooting angle, choosing focal length, determinating the depth of field, composition...
For a excellent food photographer, the crucial element is the art sense, coming from years long submerging.