Polyglycerol - Polyricinoleate PGPR

Electrostatic and non-electrostatic biopolymer complexes can also be used as effective steric stabilizers of double (multiple) emulsions. In this type of emulsion, the droplets of one liquid are dispersed within larger droplets of a second immiscible liquid (the dispersion medium for the smaller droplets of the first liquid). In practice, it is found that the so-called direct water-in-oil-in-water (W/O/W) double emulsions are more common than inverse oil-in-water-in-oil (O/W/O) emulsions (Grigoriev and Miller, 2009). In a specific example, some W/O/W double emulsions with polyglycerol polyricinoleate (PGPR) as the primary emulsifier and WPI-polysaccharide complexes as the secondary emulsifying agent were found to be efficient storage carriers for sustained release of entrapped vitamin Bi (Benichou et al., 2002). 

Figure 42 The principal structural formula of polyglycerol polyricinoleate (PGPR).

Wilson, R., Van Schie, B.J., Howes, D., 1998. Overview of the preparation, use and biological studies on polyglycerol polyricinoleate (PGPR). Food Chem. Toxicol. 36, 711-718. 

PGPR (Polyglycerol polyricinoleate, DANISCO, Denmark) was also used as emulsifier for preparing SE (W/O) and DE (W/O/W or O/W/O). PGPR is strongly lipophilic (HLB ca. 1.0), thus soluble in fats and oils, and almost insoluble in water. 

PGML Pentaglycerin monolaurate PGPR Polyglycerol polyricinoleate (E 476)... 

Figure 16 Illustration of the structural elements of PGPR. The upper stmcture is that of the polyricinoleate moiety the lower stmcture shows the polyglycerol hackhone. The R in the structure can be either hydrogen, a fatty acid residue, or a polyricinoleate residue. In PGPR at least one of the side chains is polyricinoleate.

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