Preservatives are a type of ingredient used to maintain the freshness of food products and prevent or slow spoilage.
They are able to stop spoilage occurring as a result of bacteria, moulds, fungi, or yeast. The use of antioxidants helps to delay rancidity in fats and oils and ensures cut fresh fruits, like apples, do not immediately turn brown when they are exposed to normal air.
Preservatives can also be used to make sure there are no changes in flavour, colour or texture between the production of the food item and its consumption by members of the public.
Furthermore, they can aid the control of contamination that can cause food-borne illness, such as botulism - which can potentially lead to death - and help to keep certain vitamins and nutrients in food for the benefit of the consumer.
It is likely that any processed food with a long shelf-life includes preservatives, unless it has been frozen, canned or dried.
In the US, the Food and Drug Administration (FDA) is responsible for approving and regulating the use of preservatives in food to ensure they are safe to consume.
Types of preservatives
Different groups of preservatives serve varying functions when it comes to preserving food.
Some of the main preservatives used in food products include:
• Ascorbic acid
• Citric acid
• Sodium benzoate
• Calcium propionate
• Sodium erythorbate
• Sodium nitrite
• Calcium sorbate
• Potassium sorbate
• Butylated hydroxyanisole (BHA)
• Butylated hydroxytoluene (BHT)
• Ethylenediaminetetraacetic acid (EDTA)
• Tocopherols (vitamin E)
Preservatives commonly used in meat, poultry and egg products in particular include:
• BHA
• BHT
• Tocopherols (vitamin E)
• Citric acid
• Propyl gallate
Preservative applications
Preservatives are used in a wide range of food products, including:
• Fruit sauces and jellies
• Beverages
• Baked goods
• Cured meats
• Oils and margarines
• Cereals
• Dressings
• Snack foods
• Fruits and vegetables
History
Natural preservatives have been used to keep food from spoiling for centuries.
Salt has traditionally been harnessed to preserve meat and fish, while fruit has often has its freshness maintained with the help of sugar and vegetables with vinegar.
Now many manufacturers use these ingredients along with chemical solutions to ensure their food products are kept as fresh as possible and to keep any contamination at bay.
The use of preservatives has increased in recent years as more prepared, processed and convenience foods have become available to consumers. Sugar, salt and vinegar are still used to preserve some foods made commercially.
In the US, the rules for the approval and monitoring of newly-developed preservatives are laid out in the 1958 Food Additives Amendment to the Federal Food, Drug, and Cosmetic Act and enforced by the FDA.
