How does the narrator describe the various skin tones of the brown girls?

The narrator uses food and other well-known items to describe the skin tones of the brown girls. Some girls have skin the color of 7-eleven root beer, while others are the color of the sand at Rockaway beach. Some girls are the color of soil, while others are the color of charcoal eyeliner pencils. Still others are the color of hamburger patties and others the darkest thread or as light as peanut butter.