Nano-emulsification of orange peel essential oil using sonication and native gums

Essential oils are widely used in food and pharmaceutical industries where they encounter major concerns more likely insolubility and instability. Therefore, using the response surface methodology, the influence of ultrasonication conditions as well as native gums on the mean droplets diameter (Z-average value), polydispersity index (PDI), and viscosity of the orange peel essential oil (OPEO) nanoemulsions were evaluated. In addition, the flow behavior and stability of selected nanoemulsions was assessed during storage at different temperatures. Results showed that the optimum conditions for producing OPEO nanoemulsions (12.68 nm) were determined as 94% (sonication amplitude), 138 s (sonication time) and 37 °C (process temperature). Moreover, the soluble fraction of Persian and tragacanth gums at low concentration showed significant effect on stability, particle size, and rheology. In addition, the flow behavior of produced nanoemulsions was Newtonian, and the effect of storage conditions (time and temperature) on the Z-average value was highly significant (P < 0.0001).