Characterization of β-carotene nanoemulsions prepared by microfluidization technique

Abstract

In the present work, β-carotene nanoemulsions, as potential active ingredients for liquid food, were prepared using high pressure homogenization. The influence of different homogenizing conditions (pressure and number of cycles) and emulsifier type and concentrations on particle size parameters and content of β-carotene was investigated. The droplet size of the emulsions was found to decrease from 416.0 to 97.2 nm with increasing microfluidization pressure, number of cycles, and emulsifier concentration. The optimum conditions for preparing β-carotene nanoemulsions were determined to be homogenization pressure of 120 MPa and 3 cycles. The storage study showed that the nanoemulsions were physically stable for about 5 weeks at room temperature (25°C). β-Carotene degradation was considerably slower in WPI-stabilized nanoemulsions than in Tween 20-stabilized ones, which was attributed to the increased surface area. These results have important consequences for the design and utilization of food-grade nanoemulsions.