山药对冷藏鲢鱼糜凝胶的干预作用

Intervention Effect of Yam on the Gelation of Silver Carp Surimi during Refrigerated Storage

谷氨酰胺转氨酶在低温条件下仍然可以缓慢催化鱼糜蛋白交联,形成凝胶。为缓解鱼糜贮藏过程中低温凝胶现象,考察了冷藏条件下山药对鲢鱼糜凝胶性质的影响,并探讨山药干预鱼糜低温凝胶的机理。结果表明,冷藏过程中含山药鱼糜的凝胶强度上升幅度比纯鱼糜低42%,形成的凝胶网格较松散。通过鱼糜蛋白的十二烷基磺酸钠聚丙烯酰胺凝胶电泳、傅里叶红外光谱、圆二色谱和巯基含量变化,发现含山药鱼糜的肌球蛋白重链交联量较少,蛋白构象展开程度较低,发生解旋的α-螺旋结构较少。山药可有效干预冷藏鱼糜的凝胶作用,其机理可能与影响鱼糜蛋白展开有关。

Transglutaminase can slowly catalyze protein cross-linking to form a gel even under low temperatures. To alleviate the low temperature gelation during storage, the effect of yam on the gel properties of silver carp surimi under refrigeration was investigated, and the intervention mechanism was discussed. The results showed that the growth rate of yam-surimi＇s gel strength is 42% lower than pure surimi and form a relatively looser gel. Based on the results of SDSPAGE patterns, Fourier transform infrared spectroscopy, circular dichroismspectrum and sulfhydryl group content, it was revealed that less cross-linking of myosin heavy chain（MHC）, lower degree of protein conformational changes and fewerα-helix unfolding were occurred in yam-surimi. It is concluded that yam can effectively intervene gelation during refrigerated storage, the mechanismmay relate to the effect on protein unfolding.