ABSTRACT
Fats and oils are important constituents of the human diet as a source of energy. Fats and oils are largely made of fatty acids carrying a carboxyl group (alpha end) and methyl group (omega end) with varied numbers of carbon–carbon double bonds. Based on the number and position of double bonds, fatty acids are classified as saturated, monounsaturated and polyunsaturated fatty acids. Essential fatty acids are referred to as long-chain polyunsaturated fatty acids. These fatty acids are integral constituents of cell membranes and play vital roles in various metabolic reactions. This chapter discusses the chemical structures of essential fatty acids in detail. Also, their various physical and chemical properties, viz., hydrogenation, halogenation, refractive index, melting and smoke point, are well explained. Knowledge of these physical and chemical properties aids in understanding the behavior of the fatty acids during processing and storage, and knowledge of their functional properties helps in the study of the functionality or applicability of various fatty acids in different types of processed foods.
