Oleic acid [Oil]

This is the most widely distributed of all fatty acids, found in practically every vegetable and animal fat. Rich sources are olive and peanut oils and palm olein.

Oxidation [Oil]

When oils or fats are oxidized, the unsaturated fatty acids react, resulting in rancidity. The most common mechanism of oxidation is a free radical chain reaction. This process is retarded by antioxidants such as tocopherols and tocotrienols, and accelerated by prooxidants such as trace metals and heat. The primary products of oxidation are hydroperoxides. These then decompose into secondary oxidation products such as aldehyes and ketones