Water-retaining ability of diacylglycerol

• Published in: Journal of the American Oil Chemists' Society Vol. 81; no. 10; pp. 907 - 912
• Main Author: Nakajima, Y
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.10.2004; Springer; Springer Nature B.V
• Subjects: Adsorption; Biological and medical sciences; chemical structure; DAG; diacylglycerol; diacylglycerols; emulsifying properties; emulsions; Fat industries; fatty acid; fatty acid composition; Fatty acids; Food industries; Fundamental and applied biological sciences. Psychology; Molecular structure; oil-water interface; Oils & fats; structure; w/o emulsion; water-in-oil emulsions; Water; Diacylglycerol; fatty acid; Lipids; DAG; oil/water interface; Fatty acids; Oils and fats industry; Emulsion; Oil; Structure; Interface; w/o emulsion
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1007/s11746-004-1000-x

The water‐in‐oil emulsification characteristics and the adsorption properties of DAG at the oil/water interface were investigated for DAG having different FA compositions. The water‐retaining ability of DAG is dependent on the FA composition but is not dependent on the interfacial tension at the oil/water interface in a simple way. The water‐retaining ability is very different between uni‐chain DAG (two FA have the same chain length) and complex‐chain DAG (one FA is oleic acid and the other has a shorter alkyl chain). Uni‐chain DAG, having long FA chains (R=C12 or C18∶1) have the ability to emulsify water at the volume fraction of 80% (ϕ80%), but uni‐chain DAG with short or medium chain‐length FA (R=C3, C4, C6, C8) show little ability to retain water. For complex‐chain DAG, all the DAG studied here (R1=C18∶1, R2=C2−C12) have the ability to emulsify water at ϕ80%. The stability of the emulsions, however, varies with the chain length of the R2 FA (R2 stability order: C2, C3>C18∶1, C10>C8>C4, C6). The relationship between the water‐retaining ability and the molecular structure of DAG is discussed from the viewpoint of intra‐ and intermolecular interactions between the FA chains.