谷氨酰胺转氨酶对白姑鱼鱼糜蛋白-油脂复合凝胶特性及微观结构的影响

为了探讨谷氨酰胺转氨酶(TGase)对鱼糜蛋白-脂质复合凝胶特性和微观结构的影响,研究了TGase添加量对鱼糜蛋白-脂质复合凝胶特性、水分分布状态、蛋白分子间作用力和微观结构等指标的影响。结果表明:随着TGase添加量的增加,鱼糜凝胶的硬度、咀嚼性、乳化稳定性显著性增加(P<0.05);鱼糜凝胶中非冻结水含量和凝胶持水性增加;鱼糜凝胶蛋白质分子间氢键、疏水相互作用、非二硫共价键【ε-(γ-谷氨酰基)赖氨酸共价键】等化学作用力显著性增加(P<0.05);鱼糜蛋白质电泳图谱中肌球蛋白重链(MHC)条带强度变浅。扫描电镜及其分形维数分析发现,随着TGase添加量从0%增至0.5%,鱼糜蛋白-脂质复合凝胶的分形维数从2.801增至2.857,且鱼糜蛋白质的聚集度变大,凝胶网络结构增强,进一步解释了鱼糜蛋白-脂质复合凝胶特性、乳化稳定性和持水性等增强的原因。综合分析各指标,当TGase添加量为0.4%时鱼糜蛋白-脂质复合凝胶的特性较好。

Effect of Transglutaminase on Properties and Microstructure of Surimi Protein-lipids Composite Gels

The objective of this study was to investigate the effect of transglutaminase(TGase)on gel properties,water distribution,chemical bonding indicators and microstructures of surimi protein-lipids composite gels.The results showed that adding of TGase resulted in a significant(P<0.05)increase in hardness,chewiness,emulsion stability,water holding capacity,indexes of hydrogen bonds and hydrophobic interactions,and non-disulfide covalent bond(ε-(γ-glutamyl)lysine bond)of surimi gels;and the intensity of myosin heavy chain(MHC)band became lighter with the increase of TGase concentrations.Scanning electron microscopy(SEM)images and fractal dimension analysis found that with the increase of TGase concentration from 0%to 0.5%,fractal dimension of surimi protein-lipid composite gel increased from 2.801 to 2.857,which revealed that the degree of surimi protein aggregation become more large,and gel network structure become more dense.These results further explained the mechanism of the effects of TGase on gel properties,emulsion stability and water holding capacity of surimi gels.In general,when the TGase concentration reached 0.4%,the surimi protein-lipid composite gel showed better gel properties.