Interfacial and Emulsifying Properties of Diacylglycerol

Abstract

The interfacial properties and emulsifying properties of diacylglycerol (DAG) were examined for comparison with those of triacylglycerol (TAG). The fatty acid composition and other properties of DAG were adjusted to approximately the same levels as those of TAG. The interfacial tension of DAG was about half that of TAG. When DAG was mixed with TAG, the interfacial tension of the mixture decreased in proportion to the increasing concentration of DAG and showed no breaking point. Mixtures of DAG and water were homogenized with varying oil-water proportions, with and without salt, and with and without an emulsifier. DAG was more easily emulsified than TAG and tended to become a water/oil (w/o) emulsion. The addition of salt markedly increased the stability of the DAG emulsion. DAG mixtures containing 0.25% of an emulsifier having an HLB value of between 4.5 and 13 formed w/o emulsions, while o/w emulsions were formed with TAG under the same conditions.