Effect of Salt Type on the Emulsifying Properties of Water-in-oil Emulsions Prepared with Diacyglycerol without an Emulsifier

The effect of various types of salt on the properties of water-in-oil emulsions prepared with diacylglycerol (DAG) without the addition of an emulsifier was examined. Aqueous salt solutions containing 0, 0.025, 0.05, 0.1, 0.25M and 0.5M concentrations of NaCl, KCl, CaCl_2, MgCl_2, Na_2S0_4, K_2 SO_4 and MgSO_4 were each separately used as aqueous phase. The same volume of DAG and each salt solution was emulsified at 10,000 rpm for 5 min. The emulsion stability, the particle-size distribution and the flow behavior of each emulsion were measured. The emulsion stability was markedly increased by the addition of all types of salt tested, the stability depended on salt concentration up to 0.1M. In spite of the combination of different anion, this effect was stronger for those salts having a divalent cation than a monovalent cation. On the other hand, the particle-size distribution of the all of the emulsions was similar, regardless of the type of salt or its concentration. A high salt concentration had a greater effect and increased for those salts having a divalent cation than a monovalent cation on flow behavior. From these results, we thought that divalent cations in the emulsions would have strengthened the film of the oil-water interface.6KJ00004179202論文Articledepartmental bulletin pape