Inhibition of citral degradation in an acidic aqueous environment by polyoxyethylene alkylether surfactants

Citral is a flavour component widely used in food and cosmetic industries, but is chemically unstable and degrades over time in aqueous solutions due to acid-catalysed and oxidative reactions leading to loss of desirable flavour. The present study reveals the effect of non-ionic micellar solutions of Brij30 and Brij35 on the extent of solubilisation and stabilisation of citral. The rate of chemical degradation of citral in acidic aqueous solutions was found to be highest, which was subsequently reduced significantly within these studied surfactant systems, suggesting protection of citral from an acidic environment once it is incorporated into the micelles. The work concludes that polyoxyethylene alkylether surfactants with lower HLB value, less dense hydrophilic corona and more hydrophobic core volume are efficient in solubilising and stabilising citral against an acidic environment.

► Present work reveals effect of non-ionic surfactants on stabilisation of citral.
► The aqueous solubility of citral increased appreciably within the micellar systems.
► The rate of chemical degradation of citral reduced markedly in the studied systems.
► Brij30 proved better solubilising/stabilising medium for citral than Brij35.