ABSTRACT
Lipids are chemically diverse compounds which can be extracted from animal, plant, and microbial sources with a variety of methods. The simple lipids have a fatty acid ester or ether linkage with alcohols. The majority of fatty acids in foods are straight chain, with an even carbon number. While some fatty acids are found in all foods, unusual types such as odd, branched, hydroxy, or cyclic fatty acids also exist and are primarily found in plants and microorganisms. Fatty acids can be either saturated or unsaturated. The saturated fatty acids do not contain any double bonds, while the unsaturated ones have at least one double bond. Phosphoglycerides are derivatives of glyceryl phosphoric acid. Sphingolipids contain sphingosine or a related derivative as the backbone plus a fatty acid and a polar head group. These lipids consist of ceremides, sphingomyelins, and cerebrosites.
