School of Food Technology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand.
J Food Sci. 2021 Mar;86(3):842-851. doi: 10.1111/1750-3841.15637. Epub 2021 Feb 15.
Effects of high-intensity ultrasound (HIU) treatments on gelation of threadfin bream (Nemipterus spp.) surimi at various NaCl contents (0.5, 1, and 2% NaCl) were investigated. Protein extractability at 0.5% NaCl was increased with the ultrasonic intensity (p < 0.05). At all tested NaCl contents, reactive sulfhydryl group (SH) content and surface hydrophobicity of the surimi pastes were increased after HIU treatments and were accompanied by a decrease in the Ca -ATPase activity and total SH content, indicating a greater extent of unfolding and conformational changes induced by HIU at higher NaCl contents. Textural properties and color of the surimi gels at 0.5% NaCl were improved concomitant to an increase in ultrasonic intensity (p < 0.05), whereas HIU treatments resulted in inferior gels at 1 and 2% NaCl. Scanning electron microscopy (SEM) revealed that HIU resulted in a more orderly gel network at 0.5% NaCl. Fourier transform infrared (FT-IR) spectroscopy indicated that the α-helix content of the surimi gels was decreased as the ultrasonic intensity and NaCl content increased, confirming that structural changes induced by HIU were more profound at higher NaCl contents. The results suggested that HIU technology can be applied to improve only the 0.5% NaCl surimi gel. PRACTICAL APPLICATION: High-intensity ultrasound (HIU) improved surimi gel containing 0.5% NaCl due to an increase in protein extractability and protein conformational changes. It is likely to lay a theoretical foundation for utilization of HIU technology in production of surimi-based products at low/reduced salt levels.
高强度超声（HIU）处理对不同 NaCl 含量（0.5%、1%和 2%NaCl）下牙鲆鱼糜凝胶化的影响。在 0.5%NaCl 下，随着超声强度的增加，蛋白质提取率增加（p<0.05）。在所有测试的 NaCl 含量下，HIU 处理后鱼糜糊的反应性巯基（SH）含量和表面疏水性增加，同时 Ca-ATPase 活性和总 SH 含量降低，表明在较高 NaCl 含量下，HIU 诱导的展开和构象变化程度更大。在 0.5%NaCl 下，随着超声强度的增加（p<0.05），鱼糜凝胶的质构和颜色得到改善，而在 1%和 2%NaCl 下，HIU 处理导致凝胶质量下降。扫描电子显微镜（SEM）显示，在 0.5%NaCl 下，HIU 导致更有序的凝胶网络。傅里叶变换红外（FT-IR）光谱表明，随着超声强度和 NaCl 含量的增加，鱼糜凝胶的α-螺旋含量降低，证实 HIU 诱导的结构变化在较高 NaCl 含量下更为明显。结果表明，HIU 技术仅可应用于改善 0.5%NaCl 鱼糜凝胶。实际应用：高强度超声（HIU）提高了含有 0.5%NaCl 的鱼糜凝胶的性能，这是由于蛋白质提取率增加和蛋白质构象变化所致。这可能为在低盐/低钠盐水平下利用 HIU 技术生产鱼糜制品奠定理论基础。
