College of Ocean Food and Biological Engineering, Jimei University, Xiamen 361021, China; Collaborative Innovation Center of Provincial and Ministerial Co-construction for Marine Food Deep Processing, Dalian, 116034, China.
College of Ocean Food and Biological Engineering, Jimei University, Xiamen 361021, China.
Food Res Int. 2022 Jul;157:111248. doi: 10.1016/j.foodres.2022.111248. Epub 2022 Apr 12.
Myofibrillar proteins (MPs) are susceptibly affected by ionic strength. The effect of ionic strength on the structure and emulsifying properties of MPs from hairtail (Trichiurus haumela) is still unclear. Therefore, the effect of ionic strength on the structural properties and emulsification of myofibrillar proteins from hairtail was analyzed. The increase in ionic strength led to the increase in endogenous fluorescence intensity of MPs. The α-helix content in MPs first increased and then decreased from ionic strength of 0 to 1.0 mol/L and β-sheet content exhibited the oppositive trend, indicating that α-helix in MP transformed into β-sheet. The surface hydrophobic groups of MPs increased; however, the contact angle decreased with the increase in ionic strength of 0-0.8 mol/L and a slight rebound at 1.0 mol/L. Sulfhydryl content and electrophoretic analysis further exhibited the change of MP structure at ionic strengths of 0-1.0 mol/L. Besides, the droplet size of MP emulsions was small and evenly distributed at 0.6 mol/L. Additionally, the creaming index of MP emulsions had better stability prepared at 0.6 mol/L than the other ionic strength conditions. The apparent viscosity of MP emulsions increased with the increase in ionic strength of 0-0.8 mol/L and decreased slightly at 1.0 mol/L. The rheological behavior of MP emulsions exhibited gel-like behavior without the effect of temperatures at 20-80 °C. These results can broaden the potential application of MPs from hairtail on the emulsion-type seafood products and delivery system in the food industry.
肌原纤维蛋白（MPs）易受离子强度的影响。离子强度对带鱼（Trichiurus haumela）MPs 结构和乳化性能的影响尚不清楚。因此，分析了离子强度对带鱼肌原纤维蛋白结构特性和乳化性能的影响。随着离子强度的增加，MPs 的内源荧光强度增加。MPs 中的α-螺旋含量先增加后减少，从离子强度为 0 增加到 1.0 mol/L，β-折叠含量呈相反趋势，表明 MP 中的α-螺旋转变为β-折叠。MPs 的表面疏水性基团增加；然而，接触角随着 0-0.8 mol/L 离子强度的增加而降低，在 1.0 mol/L 时略有反弹。巯基含量和电泳分析进一步表明，在 0-1.0 mol/L 的离子强度下，MP 结构发生了变化。此外，在 0.6 mol/L 时，MP 乳液的液滴尺寸较小且均匀分布。此外，在 0.6 mol/L 时，MP 乳液的 Creaming 指数比其他离子强度条件下具有更好的稳定性。MP 乳液的表观粘度随离子强度从 0 增加到 0.8 mol/L 而增加，在 1.0 mol/L 时略有下降。MP 乳液的流变行为在 20-80°C 的温度下表现出凝胶状行为，不受温度影响。这些结果可以拓宽带鱼 MP 在乳液型海鲜产品和食品工业中输送系统中的潜在应用。
