Technological and Environmental Factors Impact on the Antioxidation Mechanism of Oil Lipids

Oxidative stability of vegetable oils

Oxidative stability is the resistance of oils to oxidation during processing and storage (Guillén & Cabo, 2002). It is an important parameter to evaluate oil quality and shelf life because low molecular weight compounds are produced during oxidation. Oxidation products make the oil less acceptable or unacceptable for consumers or for industrial use as a food ingredient. Oil oxidation also destroys essential fatty acids and produces toxic compounds and oxidized polymers. Oil oxidation is very important in terms of taste, nutritional quality, and toxicity of edible oils. Different chemical mechanisms, autoxidation, and photooxidation, are responsible for the oxidation of edible oils during processing and storage, depending on the types of oxygen. Two types of oxygen can react with edible oils: atmospheric triplet oxygen, ³O₂, and singlet oxygen, ¹O₂. ³O₂ attacks lipid hydrocarbon chains and causes autoxidation, which is a free radical chain reaction. Oxidation of edible oils is influenced by energy input such as light or heat, fatty acid composition, oxygen species, and minor compounds such as metals, pigments, phospholipids, fatty acids, mono- and diacylglycerols, thermally oxidized compounds, and antioxidants. Many efforts have been made to improve the oxidative stability of oils through systematic studies on the effects of these factors (Akoh & Min, 2002).