The difference between fats and oils is the melting point, which is essentially a function of the fatty acids in the compound. Chemical Properties of Fats and Oils. Fats and oils can be hydrolyzed in the presence of acid to produce glycerol and fatty acids. During hydrogenation, some multiple bonds of unsaturated fatty acids contained in fats or oils are reacted with hydrogen and converted to single bonds. Waxes are simple lipids composed of a fatty acid esterified with a long-chain alcohol.
Waxes are insoluble in water and serve as protective coatings in nature.
Phosphoglycerides consist of glycerol esterified to two fatty acids and phosphoric acid. The phosphoglycerides are particularly important in membrane formation. These complex lipids contain a backbone of sphingosine rather than glycerol and only one fatty acid component. They are abundant in brain and nerve tissue. Membranes surround tissue cells as a selective barrier, and they encase the organelles found in eucaryotic cells.