Preservatives

The U.S. food labeling regulation defines a chemical preservative as any chemical that, when added to food, tends to prevent or retard deterioration of it. The definition leaves out common salt, sugars, vinegars, spices and oils extracted from spices. Related federal definitions describe antimicrobial agents as substances used to preserve food by preventing growth of microorganisms and subsequent spoilage, and antioxidants as substances used to preserve food by retarding deterioration, rancidity or discoloration due to oxidation.

When a chemical preservative is added, the label must state both the common name of the ingredient and its function, using words such as preservative or to retard spoilage.

In baking, preservatives are chosen to help bread, cakes and fillings last longer on the shelf. Familiar examples include calcium propionate and potassium sorbate.