Any of a class of metabolism .
They are composed of phosphate , choline , glycerol (as the ester ), and two {{link=fatty acid">fatty acids . Various fatty acids pairs distinguish the various lecithins. Commercial lecithin, a wetting and emulsifying agent used in animal feeds, baking products and mixes, chocolate, cosmetics and soap, insecticides, paint, and plastics, is a mixture of lecithins and other phospholipids in an edible oil.