Explain the composition of triglyceride.

Triglyceride is an ester derived from glycerol and three fatty acids

Glycerol is a three-carbon polyol with three hydroxyl groups that forms the backbone of a triglyceride and is chemically propane-1,2,3-triol

Each hydroxyl group of glycerol undergoes an esterification reaction with the carboxyl group of a fatty acid, releasing one molecule of water per ester bond

Fatty acids in triglycerides vary in chain length from 4 to 36 carbons but most commonly contain 12–18 carbons and can be saturated or unsaturated

Common triglyceride molecular formulas include C₅₅H₉₈O₆ for a mixed unsaturated triglyceride containing palmitic, oleic, and α-linolenic acids

Triglycerides are also known as triacylglycerols (TAGs) and are the main constituents of body fat and vegetable oils

The positions of fatty acids on glycerol are stereospecifically numbered sn-1, sn-2, and sn-3, influencing the physical properties and metabolism of the triglyceride

Saturated fatty acid residues (no double bonds) confer higher melting points and solidity, while unsaturated residues (one or more double bonds) confer lower melting points and fluidity

In biological systems, triglycerides serve as energy storage molecules that yield approximately 9 kcal per gram upon complete oxidation

Industrial applications of triglycerides include food formulations, cosmetic emollients, and biodiesel production, where their fatty acid composition determines melting behavior, oxidative stability, and flow properties