The effects of high-intensity ultrasound (20 kHz) at varying power pre-treatments (90, 120, 240, 360 and 480 W for 10 min) on foaming and structural properties of egg white were studied in this paper. The highest foaming ability (260.00%) was obtained after 360 W ultrasound treatment which was 4.9-fold to the control group. The lower viscosity and surface tension, and higher protein solubility indicated that the protein was easier to attach to the gas-liquid interface and generate molecular rearrangement. Moreover, the increased free sulfhydryl groups and surface hydrophobicity revealed that the protein adopted a loose structure after ultrasonic processing. SDS-PAGE data proved that subunit of poorly water-soluble ovomucin was declined. Scanning electron microscopy showed different microstructure with smaller aggregates and pore structure compared to non-treated egg white. These results presented more evidence of protein properties under ultrasonic environment, and broadened the application range of ultrasonic technique in food industry.

本文研究了在不同功率的预处理（90、120、240、360和480 W，持续10分钟）下高强度超声（20 kHz）对蛋清起泡和结构性能的影响。360 W超声处理后获得最高发泡能力（260.00％），是对照组的4.9倍。较低的粘度和表面张力以及较高的蛋白质溶解度表明蛋白质更易于附着在气液界面上并产生分子重排。此外，增加的游离巯基基团和表面疏水性表明该蛋白质在超声处理后呈松散的结构。SDS-PAGE数据证明水溶性差的卵粘蛋白的亚基被降低。与未处理的蛋清相比，扫描电子显微镜显示不同的微观结构，聚集体和孔结构更小。这些结果提供了更多的超声环境下蛋白质特性的证据，并拓宽了超声技术在食品工业中的应用范围。