Preservatives have been used by our ancient ancestors for centuries. Salt has long been used to preserve fish and meats. Spices and herbs preserve the flavor of foods and fruit is often preserved with sugar. Pickling cucumbers in vinegar solution is another use of preservatives. You may be surprised at the number of foods you commonly eat that contain preservatives. Your body can react to preservatives in different ways. Preservatives often cause sensitive people to experience symptoms like difficulty breathing, sneezing, skin rashes, itching or stomachaches. Some people prefer to avoid eating food containing preservatives for these reasons.

Function
According to Healthy Food Guide, preservatives are natural or artificial chemicals that are added to foods to prevent them from spoiling. You “preserve” fresh foods every day when you store them in the freezer or refrigerator. Smoking meat or fish over burning coal is another preservation method. Many packaged foods need preservatives to protect people from illnesses like food poisoning. Sugar and salt are natural preservatives.

Identification
Preservatives are a type of additive. The U.S. Food and Drug Administration requires that all additives, including preservatives, be clearly identified and labeled on food packages. If you would like to eat more natural food products, select those that are labeled “preservative-free.”

Uses
According to the U.S. Food and Drug Administration, food preservatives are most commonly used in cereals, vegetable oils, margarine, baked goods, cured meats like hot dogs, bacon and ham, snack foods and fruit condiments like sauces and jellies. They are used in dried fruit, raw prawns and cheese. Preservatives can also be found in beverages like soft drinks, wine and fruit juice.

Types
According to the American Chemical Society, there are three types of preservatives. Antimicrobials prevent bacteria, yeast and mold growth on food. Antioxidants prevent food from decomposing. A third type of preservative blocks the natural ripening of food from occurring after its harvest. There are certain preservatives that are approved for use in food by the U.S. Food and Drug Administration. These include sodium benzoate, citric acid, benzoic acid, sodium erythorbate, calcium propionate, sodium nitrite, sodium sorbate, calcium sorbate, sorbic acid, potassium ascorbate, EDTA, BHT, BHA, sulfites, ascorbic acid (vitamin C) and tocopherols (vitamin E). Different preservatives are used in different kinds of food, depending on how well they interact with other ingredients.

Warning

Some people who suffer from asthma are sensitive to the preservative sulfite. Sulfites are not approved for use in fresh foods by the U.S. Food and Drug Administration, but they are used in vinegar, dried fruits, wines and bottled lemon juice. If you are sensitive to sulfites, avoid eating food products that have potassium bisulfite, potassium metabisulfite, sulfur dioxide, sodium metabisulfite, sodium bisulfite and sodium sulfite.

Sources:

• What’s That Stuff? Food Preservatives
• What are preservatives?
• U.S. Food and Drug Administration