Fat Oxidation and Hydrolysis
Fats are composed of glycerol chemically combined as the ester of fatty acids. The fatty acids attached to the glycerol molecule can be saturated, unsaturated and polyunsaturated in any combination. Each particular fat has its own unique combination of fatty acids and therefore, its own physical and chemical properties. Saturated fatty acids are very stable because they contain no double bonds between the carbon atoms in the chain. Unsaturated fats (fats with double bonds) are subject to a variety of reactions. Monounsaturated fatty acids have one double bond while polyunsaturates have up to six double bonds and are the least stable of the fatty acids. These double bonds are the most reactive sites on the fatty acid chain and are easily attacked by oxygen, hydrogen, and enzymes. Each of these attackers produces a different result. When hydrogen reacts with the double bond, it eliminates (saturates) the bond. This process, called hydrogenation, produces a more saturated and thus more stable fat with a higher melting point. This is an industrial process that does not occur naturally during storage.