Mixed partial esters formed by reacting polymerized glycerols with edible
fats, oils, or fatty acids; minor amounts of mono-, di-, and triglycerides, free
glycerol and polyglycerols, free fatty acids, and sodium salts of fatty acids
may be present; degree of polymerization varies, and is specified by a
number (such as tri-) that is related to the average number of glycerol
residues per polyglycerol molecule. A specified polyglycerol consists of a
distribution of molecular species characteristic of its nominal degree of
polymerization. By varying the proportions as well as the nature of the fats
or fatty acids to be reacted with the polyglycerols, a large and diverse class
of products may be obtained.