The colour of food is an integral part of our culture and enjoyment of life. Even early civilizations such as the Romans recognized that people "eat with their eyes" as well as their palates. Saffron and other spices were often used to provide a rich yellow colour to various foods. Butter has been coloured yellow as far back as the 1300's.
Today, all food colour additives are carefully regulated by authorities to ensure that foods are safe to eat and accurately labeled.