ADDITIVES. Food additives are regulated substances and therefore defined in law. Unfortunately, definitions vary among jurisdictions. A typical definition of a food additive may be: a substance the use of which in a food causes it to become a part of that food or to alter the characteristics of that food. A list of exceptions (Table 1) often follows because such a definition is vague and can include many substances not normally regarded as additives. Regulations are then required that control which additives can be added to which foods, and at what levels they can be added to those foods in which they are permitted.

In the U.S. Code of Federal Regulations, Title 21—Food and Drugs (21CFR170.3), the following definition appears: "Food additives includes all substances not exempted by section 201(s) of the act, the intended use of which results or may reasonably be expected to result, directly or indirectly, either in their...