Xue Hui, Tu Yonggang, Zhang Guowen, Xin Xiaojuan, Hu Hui, Qiu Wei, Ruan Dandan, Zhao Yan
Engineering Research Center of Biomass Conversion, Ministry of Education, Nanchang University, Nanchang 330047, China.
Jiangxi Key Laboratory of Natural Products and Functional Food, Jiangxi Agricultural University, Nanchang 330045, China.
Ultrason Sonochem. 2021 Dec;81:105857. doi: 10.1016/j.ultsonch.2021.105857. Epub 2021 Dec 3.
In order to improve the characteristics of egg white protein gel and the stability of egg white protein gel products. In this work, the changes of the texture, physicochemical properties, secondary structure and microstructure of ultrasound modified egg white protein gel (UEP) and tea polyphenols (TP) assisted ultrasound modification of egg white protein gel (TUEP) with different ultrasonic power (0-360 W) were studied. With the increase of ultrasonic power, soluble protein, surface hydrophobicity and disulfide bonds of TUEP and UEP showed an increasing trend. In particular, with the increase of ultrasonic power, the content of intramolecular β-sheets and α-helices of TUEP showed an increasing trend, and significantly improved the relaxation time and microstructure, thus enhancing TUEP gel stability. In addition, the hardness and water holding capacity (WHC) of TUEP and UEP can be increased by ultrasonic treatment, and when the ultrasonic power reached 120 W, the hardness and WHC reached the maximum. The hardness and WHC of TUEP were significantly better than that of UEP. SDS-PAGE results showed that the peptide chain of protein without being broken under ultrasonic treatment. Ultrasonic treatment can improve the gel strength of egg white protein by promoting the cross-linking of proteins to form a dense gel structure, and egg white protein gel form more disulfide bonds and a more stable gel conformation under TP assisted ultrasound. In conclusion, ultrasound and TP assisted ultrasound modification of egg white protein gel is a reliable technique, which can improve the value of egg white protein in food processing.
为了改善蛋清蛋白凝胶的特性以及蛋清蛋白凝胶产品的稳定性。在本研究中，研究了不同超声功率（0 - 360 W）下超声改性蛋清蛋白凝胶（UEP）和茶多酚（TP）辅助超声改性蛋清蛋白凝胶（TUEP）的质地、理化性质、二级结构和微观结构的变化。随着超声功率的增加，TUEP和UEP的可溶性蛋白、表面疏水性和二硫键呈增加趋势。特别是，随着超声功率的增加，TUEP分子内β - 折叠和α - 螺旋的含量呈增加趋势，并显著改善了弛豫时间和微观结构，从而增强了TUEP凝胶的稳定性。此外，超声处理可提高TUEP和UEP的硬度和持水能力（WHC），当超声功率达到120 W时，硬度和WHC达到最大值。TUEP的硬度和WHC明显优于UEP。SDS - PAGE结果表明，蛋白质肽链在超声处理下未被打断。超声处理可通过促进蛋白质交联形成致密凝胶结构来提高蛋清蛋白的凝胶强度，并且在TP辅助超声作用下，蛋清蛋白凝胶形成更多二硫键和更稳定的凝胶构象。总之，超声和TP辅助超声改性蛋清蛋白凝胶是一种可靠的技术，可提高蛋清蛋白在食品加工中的价值。
