Antioxidants

Antioxidants
Antioxidants are food additives used, since about 1947, to stabilize foods that by their composition would otherwise undergo significant loss in quality in the present of oxygen. Oxidative quality changes in foods include the development of rancidity from the oxidation of unsaturated fats resulting in off-odors and off-flavors and discoloration from oxidation of pigments or other components of the food.

Although it would seem relatively simple to prevent oxidation of foods by proper packaging and precautions during handling, the facts are

• -that oxygen is difficult to exclude from food systems, especially since it is often closely associated with the food

• -that only minute amounts of oxygen are sufficient to degrade the food.

There is a large number of antioxidants and although they may function in different ways, the net effect of each is to prevent, delay, or minimize the oxidation of foods to which they are added. One of the ways by which some antioxidants function involves their combination with oxygen. Others prevent oxygen from reacting with components of the foods. When only a limited amount of oxygen present, as in a hermetically sealed container, it is possible for some antioxidants to use up all of the available free oxygen because they have a relatively great affinity for it.

Many of antioxidants used in commerce occur naturally in foods (e.g. vitamin C, vitamin E, citric acid, Amines and certain phenolics compounds). However, the amines and phenolics compounds can be toxic to humans in low concentrations; therefore, they and the synthetic antioxidants require strict regulations of their use in foods. It should be pointed out that the potency of the naturally occurring antioxidant not as great as that of the commonly used synthetic antioxidants.
Antioxidants