Emulsification of Egg Yolk Improved by Ultrasound-Assisted Soybean Protein Isolation

Abstract:

The emulsifying properties of egg yolk (EY) are easily affected by processing factors. Soy protein isolate (SPI) assisted with ultrasonic treatment was used to improve its emulsification. The emulsifying properties of EY and the properties of yolk protein improved by SPI were explored under different ultrasonic power. The results showed that the addition of SPI in EY significantly improved the emulsifying activity index (EAI) and emulsifying stability index (ESI) of EY( P<0.05). Ultrasonic power further improved the emulsification of EY-SPI. Under 150 W ultrasonic treatment, the ESI of EY-SPI emulsion was significantly higher than that of other groups( P<0.05), and the particle size and emulsification index were significantly decreased( P<0.05). The interfacial protein adsorption capacity was significantly increased( P<0.05), and the electrostatic repulsion was significantly increased( P<0.05). The emulsion droplets were more evenly distributed. Therefore, ultrasound-assisted SPI could effectively improve the emulsification of EY.