Effects of Homogenization Models and Emulsifiers on the Physicochemical Properties of -Carotene Nanoemulsions

Microfluidization and high pressure valve homogenization were applied to prepare -carotene nanoemulsions, and the mathematical relationship between homogenization pressures and emulsion temperatures, homogenization pressures/cycles, and droplet sizes, were established. Emulsions through Microfluidizer had lower temperature and much smaller droplet sizes, compared with those through high pressure valve homogenizer. Four emulsifiers were compared for their capacities to stabilize nanoemulsions. The two large molecule emulsifiers, octenyl succinate starch (OSA) and whey protein isolate (WPI), were less effective for the formation of nanoemulsions with smaller droplets than the two small molecule emulsifiers, polyoxyethylene sorbitan monolaurate (Tween 20, TW) and decaglycerol monolaurate (DML). The nanoemulsion containing WPI was the most stable, while the one containing DML was the least stable. During storage, significant degradation of -carotene occurred in all nanoemulsions, especially in the DML stabilized one, while WPI showed the greatest capacity to protect -carotene from degradation.