...Free fatty acids produced by hydrolysis can undergo auto-oxidation. Oxidation primarily occurs with unsaturated fats by free radical-mediated processes. These chemical processes can generate highly reactive molecules in rancid foods and oils which are responsible for producing unpleasant and noxious odors and flavors. These chemical processes may also destroy nutrients in the food. Under some conditions, rancidity and the destruction of vitamins occurs very quickly. Read full entry

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