Polyglycerol emulsifier

Polyglycerols obtained by the dehydration of glycerol (Scheme 3.7) are employed as surfactants, lubricants, cosmetic, food additives, etc. Their esterification with fatty acids leads also to valuable emulsifiers or metal-working fluids. Zeolites have been used to take advantage of their shape selectivity effect to minimize oligomer formation, as described in two patents [61, 62]. A fair compromise between activity and selectivity has been obtained by Clacens et al. [63] using cesium-impregnated mesoporous MCM-41. 

Table 4.6 Properties of selected polyglycerol esters as emulsifiers for personal care and food technology.

Polyglycerol polyridnoleate (E 476) Polymuls PGPR Food — emulsifier... 

Today, glycerol has over 2000 different applications, in cosmetics, pharmaceutics, foods and drinks, tobacco, paper, inks and printing colors, the production of phthalic and maleic alkyd resins and crosslinked polyesters, and as a hydraulic agent. Polyglycerols have a wide range of applications as emulsifiers, and technical esters of glycerol with fatty acids are used as synthetic lubricants [4]. 

Mean particle size ranges 50 to 1000 mn. Depending on the type and concentration of the lipid, 0.5 to 5% emulsifier (surfactant) has to be added for physical stabilization. For dermal use, surfactants are very often poloxamer 188, polysorbate 80, lecithin, tyloxapol, polyglycerol methylglucose distearate (Tegocare 450), sodinm cocoamphoacetate (Miranol Ultra C32), or saccharose fatty acid ester. 

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). 

Polyglycerol esters of fatty acids are produced by reacting polymerized glycerol with edible fats. The degree of polymerization of the glycerol and the nature of the fat provide a wide range of emulsifiers with different HLB values. 

Emulsifier Mono and diglycerides Lecithin Polyglycerol ester 0.25-1.0... 

Polyglyceryls dimers Polyglycerol esters Nonionic emulsifier, w/o emulsions... 

Powerful w/o emulsifiers such as polyglycerol polyricineolate gives stability in noncrystalline systems, such as warm emulsions, which are important in low fat spread production particularly for very low fat spreads of 20 to 25% fat content. 

Gastric lipase and pancreatic lipase are the two major triacylglyceride ester hydrolases (EC 3.1.1.3) in mammals, but they probably have no effect on the recently introduced synthetic polyglycerol esters used as emulsifiers in food and as dietetic aids (Fig. 1). 

So product developers at Danlsco Emulsifiers tailored amine-free, fatty-add-based polyglycerol esters tor use as antistats. 

Figure 19 Plot of conductivity of the outer aqueous phase (reflecting the concentration of NaCl in the outer phase (% release) vs. time (days) in three sets of double emulsions. (1) All circles indicate use of Abil EM-90 as hydrophobic Emulsifier I. The lower curves (bull) indicate the most hydro-philic PHMS—PDMS— UPEG Emulsifier II, and the upper curves (O) in each set indicate the most hydrophobic PHMS-PDMS-UPEG with 52% substitution and 45 EO units. Each circle represents a different polymeric emulsifier. (2) All triangles represent use of polyglycerol polyri-cinoleate (ETD) as Emulsifier I, and the curves are arranged again with increasing hydrophobicity of Emulsifier II. The lower curve (A) represents the most hydrophilic emulsifier, and the upper curve in the set represents the most hydrophobic one ( ). (3) AH squares represent the use of Span 80 as Emulsifier I, and the curves are arranged with increasing hydrophobicity of Emulsifier...

Chem. Descrip. Polyglycerol polyricinoleate Uses Vise, modifier In foods emulsifier In bakery release sprays flow aid reducing yield value of chocolate or coatings Properties Liq. acid no. 6 max. iodine no. 72-103 sapon. no. 170-180 ... 

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