Look at the differences between black and white and color photography.
What are the pros and cons of each? How does the lighting work? Contrast? Texture?
Notice the compositions. Notice how in Kobishop's photograph, he included a hint of a lobster on the left hand side to give the viewer clues as to what the top ingredient is in the dish. Notice in Alinat's photograph the contrast between the delicacy of the dish and the rustic background. In Anh's photograph, the background gives the image emotion.
Each image has its pros and cons, and you should analyze each photograph to see how they constructed their image and how you can use it to improve upon your own work.