NEW YORK (AP) — Six artificial flavors are being ordered out of the food supply in a dispute over their safety, but good luck to anyone who wants to know which cookies, candies or drinks they're in.

The dispute highlights the complex rules that govern what goes in our food, how much the public knows about it, and a mysterious class of ingredients that has evolved over decades largely outside of public view.

On food packages, hundreds of ingredients are listed simply as natural flavor or artificial flavor. Even in minute amounts, they help make potato chips taste oniony or give fruit candy that...