In the dehydration reaction, one molecule of glycerol and three molecules of fatty acid combine to form simple lipids called triglycerides. Triglyceride is an alcohol. It contains 3 carbon and 3 hydroxy groups. Fatty acids are hydrocarbon chains and contain carboxyl groups. Linkage of OH side group through dehydration reaction of carboxyl group is called ester linkage. There are two types of triglycerides. Saturated or unsaturated and unsaturated. Dr. Siddiq Publications