Molecular forces involved in heat-induced freshwater surimi gel: Effects of various bond disrupting agents on the gel properties and protein conformation changes
Molecular forces involved in heat-induced freshwater surimi gel: Effects of various bond disrupting agents on the gel properties and protein conformation changes
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DOI：
10.1016/j.foodhyd.2017.02.003
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发表时间：
2017-08
影响因子：
10.7
通讯作者：
Nannan Yu;Yanshun Xu;Q. Jiang;W. Xia
中科院分区：
文献类型：
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作者：
Nannan Yu;Yanshun Xu;Q. Jiang;W. Xia
采用尿素、十二烷基硫酸钠（SDS）和N-乙基马来酰亚胺（NEM）对鱼糜热凝胶中氢键、疏水作用和二硫键的贡献进行了研究。鱼糜凝胶的制备与键断裂剂，随后的质地，凝胶强度，流变学和拉曼分析。流变学分析表明，在临界温度以下，储能模量（G′）发生了显著变化，特别是SDS处理。凝胶强度随尿素和NEM浓度的增加而显著降低，而1%SDS则略有提高。破键剂的加入使鱼糜凝胶的硬度和胶粘性显著降低。拉曼光谱结果表明，蛋白质二级结构有向无规卷曲转变的趋势，α-螺旋和β-折叠含量减少。质构特性与蛋白质构象相关。无规卷曲的减少导致凝胶强度的提高，弹性主要由β-折叠和β-转角贡献。结果表明，不同的键断裂剂引起不同的鱼糜凝胶特性和蛋白质二级结构的变化。
Urea, sodium dodecyl sulfate (SDS) and N-ethylmaleimide (NEM) were employed to monitor the contributions of hydrogen bonds, hydrophobic interactions and disulfide bonds in heat-induced surimi gel. Surimi gels were prepared with the bond disrupting agents followed by texture profile, gel strength, rheological and Raman analysis. The rheological analysis demonstrated that remarkable changes of storage moduli (G′) were presented below the critical temperature, especially for SDS treatments. Gel strength significantly decreased as the concentration of urea and NEM increased, while it was slightly improved by 1% SDS. With the involvement of bond disrupting agents, hardness and gumminess of surimi gel presented a dramatical decrease. The Raman results indicated that protein secondary structure tended to transform to random coil, with content of α-helix and β-sheet decreasing. Textural properties were in correlation with protein conformation. Less of random coil led to improvement of gel strength, and springiness was mainly contributed by β-sheet and β-turn. The results suggested that different bond disrupting agents induced various changes in surimi gel properties and protein secondary structure.