Changes in lipid compositions of krill oil emulsions during storage, a role of ultrasound treatment and the possible process of lipid migration

Summary The changes in lipid compositions of krill oil emulsions during storage were investigated, as well as the role of ultrasound treatment. Whey protein isolate (WPI) was used as wall materials to krill oil, which was treated with ultrasound. The effects of WPI concentration (from 0.2% to 10%), ultrasound power (from 10% to 80%) and treatment (at the same energy density with different power) were evaluated. Storage stability of different emulsions was characterised appearance, particle sizes, zeta potential, polydispersity index and microstructures. The lipid compositions and interactions were analysed to debate the changes of emulsions. The results indicated that ultrasound increased the stability of emulsions, enhanced the hydrophobic interactions between WPI and lipids and kept lipid composition distributions in each layer of emulsions. Furthermore, a possible mechanism of lipid migration in krill oil emulsions was put forward. The study will assist in the application and mechanism of krill oil emulsions treated with ultrasound.