摘要
蛋黄在-6℃以下冷冻贮藏会发生胶凝化现象,影响其在食品加工中的应用。本实验通过流变特性表征了冻藏180 d内蛋黄的胶凝化现象,并进一步通过理化性质、水分分布以及二级结构分析探究蛋黄胶凝化的成因。结果发现冻藏期间蛋黄表观黏度、黏性系数、弹性模量和黏性模量均显著增加,而流动指数和损耗角正切值显著减小,表明冷冻导致了蛋黄严重的胶凝化。平均粒径的增加、表面疏水性的增强、总巯基含量的下降、蛋黄水分分布的变化尤其是可冻结水含量的减少,都会导致蛋黄胶凝化;同时蛋黄蛋白质二级结构从无序向有序转变,也促进了蛋黄蛋白质的聚集,进一步诱导蛋黄胶凝化。本研究探究蛋黄胶凝化的原因,为进一步改善蛋黄在冷冻过程中出现胶凝化提供参考。
Yolk gelation occurs when stored at temperatures below ？6 ℃, which will affect yolk application in food processing. The gelation of yolk frozen for 180 d was characterized by rheological properties, and the physicochemical properties, water distribution and secondary structure were analyzed to further explore the cause of yolk gelation. Apparent viscosity, viscosity coefficient （K） value, elasticity modulus （G’） and viscous module （G’’） in yolk were significantly increased, while flow index （n） value and loss tangent （tan δ） were significantly decreased during frozen storage, suggesting that freezing led to serious gelation of yolk. Yolk gelation was caused by the increased average particle size and surface hydrophobicity, the decreased total sulfhydryl and the change in moisture distribution, and especially by the reduced freezable water content in yolk; meanwhile, the secondary structure transformation from a disordered to an ordered state of yolk proteins also promoted yolk protein aggregation and consequently induced yolk gelation. The cause of yolk gelation reported in this study provides a theoretical basis for further improving yolk gelation during freezing process.
作者
闫峥蓉
赵英
迟玉杰
YAN Zhengrong;ZHAO Ying;CHI Yujie(College of Food Science,Northeast Agricultural University,Harbin 150030,China)
出处
《食品科学》
EI
CAS
CSCD
北大核心
2018年第19期29-35,共7页
Food Science
基金
现代农业产业技术体系建设专项(CARS-40-K25)
关键词
蛋黄
冻藏
胶凝化
成因分析
yolk
frozen storage
gelation
causal analysis
