Phase properties and structure of a monoglyceride/sucrose/water system

✍ Scribed by Ingrid Söderberg; Helena Ljusberg-Wahren

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 324 KB
• Volume: 55
• Category: Article
• ISSN: 0009-3084
• DOI: 10.1016/0009-3084(90)90070-8

✦ Synopsis

The phase behaviour of a sunflower oil, monoglyceride/sucrose/water system was studied at 30°C. The different phases were identified by low-angle X-ray diffraction and polarization microscopy. The main feature of the phase diagram is the transition from a cubic phase to a reversed hexagonal phase (HH) when sucrose is added to the monoglyceride/water mixture. A similar phase behaviour was also shown to occur for monoolein/sucrose/water, as well as in the corresponding systems when sucrose was replaced by trehaiose, fructose and glucose, respectively.

The phase transition from a cubic phase to a H~ phase, when sugar is introduced to a monoglyceride/water system, corresponds to an increased average wedge shape of the lipid molecule. One explanation for this phenomenon is a structural change of the lipid caused by interaction between the sugar and the hydrated polar head group, thus reducing the interfacial area of the polar region at the contact zone with water.