Effect of microwave-ultrasonic combination treatment on heating-induced gel properties of low-sodium tilapia surimi during gel setting stage and comparative analysis
Yuehua Ye, Xiaoyan Liu, Weidong Bai, Wenhong Zhao, Ying Zhang, Hao Dong, Zhenhui Pan
Abstract
To improve the gel properties of low-sodium tilapia surimi, the effects of microwave-ultrasonic, single microwave, single ultrasonic and traditional water-bath heating treatments on the characteristics of low-sodium tilapia surimi gel in the gel setting stage were investigated in this study. Compared with other treatment groups, the water-bath heating and microwave–ultrasonic-assisted heating (WB-MW/US) + 1.5% NaCl group had higher gel strength (403.30 g cm) and water-holding capacity (87.88%). LF-NMR and CD spectrum analysis indicated that microwave and ultrasonic combination increased the degree of protein cross-linking and moisture proton density. In addition, microwave and ultrasonic combination had minimal effect on the secondary protein structure. WB-MW/US+1.5% NaCl group had more β-sheet (27.80%) and random coil content (22.30%), resulting in a uniform and dense spatial network structure of the low-sodium tilapia surimi gel. The results indicated that the microwave-ultrasonic combination treatment could be used as an efficient strategy for the production of new energy, low-sodium surimi gel products.