A tortilla chip is a snack food made from corn tortillas, which are cut into wedges and then fried—or baked (alternatively they may be discs pressed out of corn masa then fried or baked). Corn tortillas are made of corn, vegetable oil, salt and water. Although first mass-produced in Los Angeles in the late 1940s, tortilla chips were always considered to be a Mexican food, known as totopos and tostadas. Though usually made of yellow corn, they can also be made of white, blue, or red corn. Some manufacturers include many other ingredients including wheat, sugar, food colouring, and monosodium glutamate.