 The foam is a good thermal insulator, making the container easy to carry as well as keeping the food at the temperature it had when filled into the container, whether hot or cold.Foam take-out containers are made from expanded polystyrene (EPS) foam, or another type of polystyrene foam, and produced by injecting the foam into a mold.They are usually white in color, although they may be printed or impressed with a company logo or other message.