Optimisation of conditions for the preparation of β-carotene nanoemulsions using response surface methodology

Response surface methodology (RSM) was used to optimise the conditions for preparing beta-carotene nanoemulsions. The effects of beta-carotene (0.2-1.8%, w/w) and emulsifier (6.9-13.1%, w/w) concentrations, the homogenization pressure (79.1-140.9 MPa) and temperature (34.5-65.5 degrees C) on the particle size and stability of the nanoemulsions were studied. Results showed that the experimental data could be adequately fitted into a second-order polynomial model with multiple regression coefficients (R-2) of 0.921 and 0.981 for the particle size and stability, respectively. Homogenization pressure and beta-carotene concentration and the quadrics of beta-carotene concentration (P < 0.05) had a significant effect on the particle size of the nanoemulsions. Homogenization temperature and pressure, beta-carotene concentration, the quadrics of emulsifier concentration and the interactions between beta-carotene and emulsifier concentrations and between homogenization temperature and emulsifier concentration (P < 0.05) had a significant effect on the stability of the emulsions. The optimum conditions for preparing beta-carotene nanoemulsions were predicted to be: homogenization pressure, 129 MPa; homogenization temperature, 47 degrees C; beta-carotene concentration, 0.82%; emulsifier concentration, 8.2%. (c) 2007 Elsevier Ltd. All rights reserved.