Antioxidants: Regulatory Status

Abstract

Oxidation of unsaturated lipids is a major cause of food quality deterioration by giving rise to the development of off-flavor compounds and loss of nutritional value of food products. Although it has been known for a long time that lipid oxidation can be induced by catalytic systems such as light, temperature, enzymes, metals, and metalloproteins; the mechanism of oxidation reactions remained uncertain until the 1940s when free radicals and reactive oxygen species were found to be involved in oxidation processes by the pioneering work of Farmer et al. Furthermore, antioxidants were found to protect lipids against oxidation either by quenching free radicals or scavenging oxygen, among others. Antioxidants are substances that, when present in foods at low concentrations compared with that of an oxidizable substrate, markedly delay or prevent the oxidation of the substrate. Antioxidants that fit in this definition include free radical scavengers, inactivators of peroxides, and other reactive oxygen species (ROS), chelators of metals, and quenchers of secondary lipid oxidation products that produce rancid odors. Antioxidants have also been used in the health-related area because of their ability to protect the body against damage caused by ROS as well as reactive nitrogen species (RNS) and those of reactive chlorine species (RCS). Keywords: antioxidants; regulations; bha; bht; tbhq; gallates; ascorbic acids; synthetic antioxidants; natural antioxidants; tocapherols; tocotrienols; carotenoids