Food additives may be natural or synthetic. For example, vitamin C is a natural preservative. Butylated hydroxyanisole (BHA) and butylated hydroxytoluene(BHT) are synthetic preservatives. To ensure your safety, both the natural and synthetic food additives used in the United States come only from the group of substances known as the generally recognized as safe (GRAS) list.
All additives on the GRAS list
Vitamin D, which is added to virtually all milk sold in the United States, is one example of a clearly beneficial food additive. Most U.S. bread and grain products are fortified with added B vitamins, plus iron and other essential minerals to replace what's lost when whole grains are milled into white flour for white bread. Some people say that people would be better off simply sticking to whole grains, but adding vitamins and minerals to white flours enhances a product that many people prefer.
Some nutrients are also useful preservatives. For example, vitamin C is an antioxidant that slows food spoilage and prevents destructive chemical reactions, which is why American food packagers must add a form of vitamin C (isoascorbic acid or sodium ascorbate) to bacon and other luncheon meats to prevent the formation of potentially cancer-causing compounds.
Colors, flavoring agents, and flavor enhancers make food look and taste better. Like other food additives, these three may be either natural or synthetic.
One good example of a natural coloring agent is beta carotene, the yellow pigment extracted from many fruits and vegetables and used to turn naturally white margarine to buttery yellow.
Some other natural coloring agents are annatto, a yellow-to-pink pigment from a tropical tree; chlorophyll, the green pigment in green plants; carmine, a reddish extract of cochineal (a pigment from crushed beetles); saffron, a yellow herb; and turmeric, a yellow spice.
An example of a synthetic coloring agent is FD&C Blue No. 1, a bright blue pigment made from coal tar and used in soft drinks, gelatin, hair dyes, and face powders, among other things.
And, yes, as scientists have discovered more about the effects of coal-tar dyes, including the fact that some are carcinogenic, many of these coloring agents have been banned from use in food in one country or another but are still allowed in cosmetics.
Every cook worth his or her spice cabinet knows about natural flavor ingredients, especially salt, sugar, vinegar, wine, and fruit juices.
Artificial flavoring agents reproduce natural flavors. For example, a teaspoon of fresh lemon juice in the batter lends cheesecake a certain je ne sais quoi (French for "I don't know what" — a little something special), but artificial lemon flavoring works just as well. You can sweeten your morning coffee with natural sugar or with the artificial sweetener saccharin.
Flavor enhancers are a slightly different kettle of fish. They intensify a food's natural flavor instead of adding a new one. The best-known flavor enhancer is monosodium glutamate (MSG), widely used in Asian foods.
Although it improves flavor, MSG may also trigger short-term, generally mild reactions, such as headaches, flushing, sweating, facial numbness and tingling, and rapid heartbeat in people sensitive to the seasoning.
Food spoilage is a totally natural phenomenon. Milk sours. Bread molds. Meat and poultry rot. Vegetables wilt. Fats turn rancid. The first three kinds of spoilage are caused by microbes (bacteria, mold, and yeasts). The last two happen when food is exposed to oxygen (air).
Preservative techniques such as cooking, chilling, canning, freezing, and drying prevent spoilage either by slowing the growth of the organisms that live on food or by protecting the food from the effects of oxygen. Chemical preservatives do essentially the same thing:
The table is a representative list of some common preservative chemicals and the foods in which they're found.
* A form of vitamin C
Food chemists use a variety of the following types of natural and chemical additives to improve the texture of food or prevent mixtures from separating:
Although many of these additives are derived from foods, their benefit is aesthetic (the food looks better and tastes better), not nutritional.
Carol Ann Rinzler is a former nutrition columnist for the New York Daily News and the author of more than 30 health-related books, including Controlling Cholesterol For Dummies, Heartburn and Reflux For Dummies, The New Complete Book of Food, the award-winning Estrogen and Breast Cancer: A Warning for Women, and Leonardo’s Foot, which the American Association for the Advancement of Science described as “some of the best writing about science for the non-scientist encountered in recent years.”