Influence of structural properties of emulsifiers on citral degradation in model emulsions

  • Sung Hwa Kim
  • Ha Youn Song
  • Seung Jun ChoiEmail author


The storage stability of compounds encapsulated in emulsions is strongly influenced by the properties of the droplet interfacial membrane. To evaluate the effect of emulsion droplet interface thickness on the degradation of citral, emulsions were prepared using polyoxyethylene alkyl ether-type emulsifiers with hydrophilic and hydrophobic groups of various sizes. Acid cyclization of citral at pH 3 promoted faster degradation than that at pH 7. Ferrous irons accelerated citral degradation in the emulsions at pH 3 but not at pH 7, because they decomposed the products of the acid-catalyzed cyclization of citral through redox reactions rather than direct degradation. Water-soluble radicals dramatically increased the rate of citral degradation, irrespective of pH. Notably, at low pH, the rate of citral degradation by ferrous irons was higher than that by radicals. These findings suggest that the thickness and density of emulsion droplet surfaces are not important factors for inhibiting citral degradation in emulsions.


Citral Degradation Emulsions Interfacial characteristics Interfacial membrane 



This work was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2016R1D1A1B03930215), Republic of Korea.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© The Korean Society of Food Science and Technology 2018

Authors and Affiliations

  1. 1.Department of Food Science and TechnologySeoul National University of Science and TechnologySeoulRepublic of Korea
  2. 2.Department of Agricultural BiotechnologySeoul National UniversitySeoulRepublic of Korea
  3. 3.Department of Interdisciplinary Bio IT MaterialsSeoul National University of Science and TechnologySeoulRepublic of Korea

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