圆苞车前子壳粉对鱼糜凝胶热稳定性的影响及机理研究

The effect of psyllium husk powder on the thermal stability of surimi gel and its mechanisms

为改善鱼糜凝胶的热稳定性,该文通过控制圆苞车前子壳粉(psyllium husk powder,PHP)添加量(0.25%、0.5%、0.75%和1%,质量分数),研究其对高温处理的冷冻鳕鱼鱼糜凝胶品质(质构、动态流变学特性、微观结构)的影响,并进一步通过差示扫描量热仪、低场核磁、拉曼光谱等分析手段,阐述圆苞车前子壳粉增强鱼糜凝胶热稳定性的机制。结果表明,疏水相互作用和二硫键是维持鱼糜凝胶热稳定性的主要作用力;随PHP添加量增加,鱼糜凝胶强度、硬度、持水性、储能模量和热变性温度均呈现先上升后下降趋势,且PHP添加量为0.5%时达到最大值,凝胶微观结构更为致密均一。拉曼图谱显示,添加PHP可以改变蛋白质二级结构,促使鱼糜蛋白的α-螺旋结构向β-折叠和无规则卷曲转变。水分分布结果显示,添加PHP能降低凝胶中水分自由度,促使自由水向不易流动水和结合水转变。综上所述,添加一定量的圆苞车前子壳粉(0%~0.5%)可以显著提高鱼糜凝胶热稳定性。该研究可为进一步提高鱼糜凝胶品质以及丰富鱼糜制品的加工品类提供参考。

In this work,the effects of various dosages(0.25%,0.5%,0.75% and 1%) psyllium husk powder(PHP) on the gel properties(texture,dynamic rheological properties,and microstructure) of cod surimi gel were investigated.Furthermore,the corresponding mechanisms were also explored by thermal denaturation temperature,low field nuclear magnetic field and Raman spectroscopy.The results showed that hydrophobic interaction and disulfide bond were the main forces to enhance the thermal stability of surimi gel.The gel strength,hardness,water holding capacity,storage modulus(G′) and thermal denaturation temperature of surimi firstly increased and then decreased with the addition of PHP.The maximum values were achieved with the addition of 0.5% PHP.Raman spectra showed that PHP promoted the transformation of the α-helix structure into the β-fold and irregular curl.The addition of PHP also reduced the degree of freedom of water within the gel by accelerating the change of free water to uneasily flowing water and bound water.In conclusion,the addition of psyllium husk powder(0%-0.5%) could significantly improve the thermal stability of surimi gel to some extent.This study provides a guideline for the development of surimi gel products.