Triglycerides

Triglycerides - the fats and oils of everyday diet - are composed of a single glycerol molecule bound to three fatty acid chains. Each fatty acid is a long-chain hydrocarbon carrying a carboxyl group at one end; this carboxyl group reacts with one of glycerol's hydroxyl groups to form an ester bond, and this happens three times over to attach all three fatty acids to the one glycerol backbone. Fatty acid hydrocarbon chains can range in length from about 4 to 24 carbon atoms, and may be saturated (every carbon-carbon bond in the chain is a single bond, e.g., palmitic acid, stearic acid) or unsaturated (the chain contains one or more carbon-carbon double bonds, e.g., oleic acid, linoleic acid). As a general rule, fats built from mostly saturated fatty acids are solid at room temperature, while those built f …