通过研究鲢肌球蛋白二级结构和二硫键、非二硫共价键、疏水相互作用这3种主要化学作用力随温度的变化及其聚集行为,探讨鲢肌球蛋白胶凝过程中的动态流变行为变化的机理.研究表明:在35～55℃温度内,肌球蛋白变性引起尾部的α-螺旋大量解旋,尾部疏水性侧链暴露,表面疏水性大幅度增加,同时肌球蛋白分子头部-SH氧化形成二硫键,溶解度大幅度下降,非二硫共价键大量形成;在55～ 80℃温度区间内,肌球蛋白的表面疏水性、二硫键含量继续小幅增加,而非二硫共价键含量降低.在28.4～37℃和40.3 ～69℃这2个温度区间内储藏模量增加,由1.08 Pa增加至246.90 Pa,而其余温度区间储藏模量降低.3种化学作用力在不同温度区间对储藏模量的贡献不同,在28.4 ～37℃和40.3～50℃这2个温度区间内,3种化学作用力均随温度的增加而大幅度增加;在50～69.5℃温度区间内,二硫键和疏水相互作用依然随温度增加而增加,但是非二硫共价键随之降低.

Myosin was the main protein in carp gel.The dynamical rheological behavior of myosin from silver carp was investigated by measuring the changes of secondary structure,three main chemical interactions including disulfide bond,non-disulfide covalent bond and hydrophobic interaction,and aggregation behavior.Myosin tail denatured and α-helix unfolded drastically in the range of 35 ～ 55℃.Its surface hydrophobicity increased dramatically after hydrophobic side chains of denatured myosin were exposed and myosin molecules aggregated.At this temperature,the sulfhydryls in myosin head were oxidized and converted to disulfide bond.In the range of 55 ～ 80 ℃,disulfide bond and surface hydrophobicity also increased slowly.Nevertheless,non-disulfide covalent bond decreased.During the formation of myosin gel,storage modulus increased at the following two temperature range,28.4 ～ 37 ℃ and 40.3 ～ 69 ℃,from 1.08 Pa to 246.90 Pa.The contributions of these chemical interactions on storage modulus were different at different temperature ranges.In 28.4 ～ 37 ℃ and 40.3 ～ 50 ℃ ranges,all these chemical interactions increased dramatically with temperature increasing.In the 50 ～ 69.5 2 range,with increased temperature,disulfide bond and hydrophobic interaction increased,but non-disulfide covalent bond decreased.