Oxidation of Lipids in Foods

Lipid oxidation is a major cause of deterioration in the quality of food and food products. Oxidationcan occur in both triglycerides and phospholipids of food because lipids are divided into two main classes; polar lipids (phospholipids) and neutral lipids (triglycerides). Lipid oxidation has been long been recognized as a major problem in the storage of fatty acids in foods. Oxidation occurs by several molecular mechanisms such as generation of reactive oxygen precursors and free radicals. Oxidation affects many interactions among food constituents, leading to both desirable and undesirable products. Food lipids are the foods components that are most susceptible to oxidation, therefore oxidation reactions are one of the major sources of deterioration that occurs during manufacturing, storage, distribution and final preparation of foods. Lipid oxidation products are omnipresent in foods, although much variation exists in their kind and levels present. Although levels of these compounds are generally low, the problem of lipid oxidation severely compromises the quality of some food products and limits the shelf-life of others. Oxidative changes can cause rancidity such as off flavours, loss of colour, altered nutrient value, and may produce toxic compounds, which can be detrimental to the health of consumers. Antioxidants and chelating agents are the most helpful inhibitors of lipid oxidation.