Improvement of physical stability of kenaf seed oil-in-water nanoemulsions by addition of β-cyclodextrin to primary emulsion containing sodium caseinate and Tween 20

In this study, kenaf (Hibiscus cannabinus L) seed oil-in-water nanoemulsions stabilized with sodium caseinate, Tween 20 and beta-cyclodextrin complexes were produced using high pressure homogenizer. Emulsifying conditions, including concentration of optimized emulsifier mixtures and the addition sequence of beta-cyclodextrin (beta-CD) were studied. In addition, process parameters, namely homogenization pressure (16,000-28,000 psi) and homogenization cycles (3-5 cycles) were optimized to produce high physical stability of kenaf seed oil-in-water nanoemulsions. Emulsifier concentration of 10% (w/w) with beta-CD on the primary emulsion was successfully optimized, which showed great enhancement on the stability of kenaf seed oil-in-water nanoemulsions to environmental stresses. The optimized process parameters was found to be 28,000 psi for 4 cycles, which produced nanoemulsions with 122.2 nm, 0.147, and -46.6 mV of particle size, PDI, and zeta-potential, respectively. It showed good stability for up to 6 weeks of storage at 25 degrees C +/- 2 degrees C. The present study showed that the production of stable kenaf seed oil-in-water nanoemulsions using high pressure homogenizer is feasible and potential for large scale manufacturing. (C) 2016 Elsevier Ltd. All rights reserved.