Fatty acids are carboxylic acids that are structural components of fats, oils, and all other categories of lipids, except steroids. Fatty acids usually contain an even number of carbon atoms, are generally unbranched, and can be classified by the presence and number of carbon-to-carbon double bonds. Thus, saturated fatty acids contain no carbon-to-carbon double bonds, monounsaturated fatty acids contain one carbon-to-carbon double bond, and polyunsaturated fatty acids contain two or more carbon-to-carbon double bonds.
Figure 1. Cis-and-trans-fatty-acids
16- and 18-carbon fatty acids are the most widely distributed fatty acids, otherwise known as palmitic acid and stearic acid, respectively. Both palmitic and stearic acids occur in the lipids of the majority of organisms. In animals palmitic acids make up as much as 30% of body fat. It accounts for anywhere from 5-50% of lipids in vegetable fats, being especially abundant in palm oil. Stearic acid is abundant in some vegetable oils and makes up a relatively high proportion of the lipids found in ruminant tallow.
Fatty acid esters (FAEs) are a type of ester that result from the combination of a fatty acid with an alcohol. When the alcohol component is glycerol, the fatty acid esters produced can be monoglycerides, diglycerides, or triglycerides. Dietary fats are chemically triglycerides.
Figure 2. Synthesis of FAME
The molecule complexity of fatty acids and their derivatives allows that hydrogenation occurs in two different parts of the molecule: in the unsaturated hydrogenation chain or in the organic functional group of carbon I. Although there are some continuous described processes, most of hydrogenation reactions are carried in batch reators.
The following equations show the dehydrogenations of fatty acids and their derivatives
Figure 3. Dehydrogenation of fatty acids and their derivatives
The presence of one or more unsaturation along the hydrocarbonate chain can give place to an important amount of isomers by isomerization reaction of fatty acids and their derivatives. Lately isomerization of fatty acids and their derivatives has significantly become more interesting due to the recent research concerning the conflicting human effect of trans isomers. However, some of them are associated to anticarcinogenic and antioxidative effects.
Fatty acids and their derivatives have a wide range of commercial applications. For example, they are used not only in the production of numerous food products but also in soaps, detergents, and cosmetics. Soaps are the sodium and potassium salts of fatty acids. Some skin-care products contain fatty acids, which can help maintain healthy skin appearance and function. Fatty acids, particularly omega-3 fatty acids, are also commonly sold as dietary supplements. And they can also be used in industrial applications such as lubricants, pharmaceutical and plastics.
Figure 4. Application of fatty acids and their derivatives
Alfa Chemistry offers a variety of fatty acids and ester for customers to choose from.