Interactions at the interface between hydrophobic and hydrophilic emulsifiers: Polyglycerol polyricinoleate (PGPR) and milk proteins, studied by drop shape tensiometry
- 作者：陌brahim Gü ; lseren ; igulsere@uoguelph.ca ; Milena Corredig
- 关键词：Polyglycerol polyricinolate (PGPR) ; Drop shape tensiometry ; Dilational elasticity ; Sodium caseinate ; 尾-Lactoglobulin
- 刊名：Food Hydrocolloids
- 出版年：2012
- 期刊代码：37_0268005x
- 类别：ch
- 出版时间：October, 2012
- 卷：29
- 期：1
- 页码：193-198
- 文件大小：299 K
摘要
The equilibrium interfacial tension and dilational elasticity at the soy oil-water interface were studied in the presence of a lipophilic emulsifier, polyglycerol polyricinoleate (PGPR), in the continuous oil phase, and dairy proteins, 尾-lactoglobulin (尾-lg) or sodium caseinate, in the aqueous phase using drop shape tensiometry. The interfacial tension decreased with increasing PGPR concentration, and was <2聽mN聽m鈭? at PGPR concentrations beyond 1%. The presence of proteins in the water phase, 尾-lg and sodium caseinate, further reduced the interfacial tension. Even at the low concentrations (0.008%) tested, PGPR dominated the interfacial elasticity, which was only slightly affected by the addition of elevated levels of protein. While in the presence of 尾-lg (0.1%) in isolation, the system showed a high interfacial elasticity, the addition of PGPR lowered the elasticity, suggesting that PGPR interfered with protein-protein interactions at the interface, or caused displacement of 尾-lg. Interfacial elasticity at the oil-water interface showed little dependence on dilation or frequency of the sinusoidal oscillation, when the interface was dominated by PGPR.