Yolanda Winitsky, age 14, of Decatur, Ill., for her question:
ARE MANY KINDS OF ADDITIVES PUT INTO FOOD?
A food additive is any chemical that food manufactures intentionally add to one of their products. Some additives increase the food's nutritional value, while others improve color, flavor or textures. Others keep foods from spoiling.
Food manufacturers actually use hundreds of additives in processing various foods. They can be grouped into six major classifications: preservatives, nutritional supplements, flavoring agents, coloring agents, emulsifiers (including stabilizers and thickeners), and acids and alkalis.
Preservatives, such as salt, prevent the growth of bacteria that cause food to spoil. Preservatives called "antioxidants" keep fats and oils from spoiling and prevent other foods from becoming discolored.
Nutritional supplements, such as iron, minerals and vitamins, make some foods more nourishing. Vitamin B 1 and vitamin B 2 are often added to flour and some milk has vitamin D added.
Flavoring agents include all spices and natural fruit flavors as well as man made flavors. Some agents, such as monosodium glutamate (MSG) add no flavor of their own but improve a food's natural flavor.
Coloring agents make synthetic foods resemble real ones. Manufacturers also add coloring to many canned foods to replace natural food colors that are lost in processing. Some coloring agents, such as the orange color sometimes added to the skins of some oranges, improve the appearance of a food.
Emulsifiers, stabilizers and thickeners help the ingredients in a food to mix and hold together. For example, pectin and gelatin thickens jams and jellies.
Acids and alkalis help maintain a chemical balance in some foods. For example, citric acid added to fruit juice gives it a tart taste. Carbonic acid puts the fizz in some soft drinks.
In the United States, the Federal Food, Drug and Cosmetic Act of 1938 sets standards for the food industry and requires truthful labeling.
Laws require a manufacturer to prove that a new food addititive is completely safe before it can be used.
The Food and Drug Administration (FDA) enforces the 1938 act.
The act also prohibits the use of any food additive if that chemical causes cancer in animals. Such additives have been banned because of concern that they might also cause cancer in human beings.
In 1970, the FDA prohibited the sale of artificial sweeteners called cyclamates. Experiments had shown that cyclamates caused cancer in rats when fed to animals in large amounts.