Triglyceride
An ester formed from glycerol and three fatty acid molecules, the main constituent of fats and oils.
Formula / equation
glycerol + 3 RCOOH
Unit
Dimensionless
In depth
Triglycerides are the body's principal energy store, yielding about 38 kJ/g. Whether one is a solid fat or a liquid oil depends on its fatty acids: saturated chains pack tightly and raise the melting point, while cis unsaturated chains have kinks that prevent close packing.
Examples in the real world
Animal fats rich in saturated chains; vegetable oils rich in unsaturated ones; both saponify to give soap.