摘要
采用激光共聚焦显微拉曼光谱仪及低场核磁共振成像分析仪对冻结过程中面团面筋蛋白分子结构变化规律和水分迁移进行原位表征和分析。结果表明:45%加水量面筋蛋白二硫键构型最为稳定,二硫键gauche-gauchegauche(g-g-g)构型的相对含量在冻结后下降了4.33%,冻结过程中,相对稳定的g-g-g构型向不稳定的gauchegauche-trans(g-g-t)和trans-gauche-trans(t-g-t)构型转化;代表氨基酸侧链微环境的拉曼图谱中740 cm^(-1)与1004 cm^(-1)处吸收峰的比值(I_(740/1004))在面团加水量45%时达到最大值,并在冻结过程中持续下降;不同加水量面筋蛋白在冻结终点时,二级结构中α-螺旋相对含量并无明显差异,随着温度下降α-螺旋相对含量下降3.63%;水分分布及水分迁移的结果表明,面团冻结过程中,由冰晶生长引起的品质劣变随着加水量的增加更早出现。本研究从微观尺度和分子水平揭示了面团冻结过程中面筋蛋白结构和水分的变化规律,阐明了面团冻结过程中品质劣变的机理。
In this experiment,confocal laser Raman spectroscopy and low-field nuclear magnetic resonance imaging were used to in situ characterize and analyze the molecular structure changes of gluten proteins and water migration during the freezing process of dough.The results showed that the disulfide bond configuration of gluten proteins in dough with 45%water content was the most stable,and the relative percentage of the gauche-gauche-gauche(g-g-g)configuration decreased by 4.33%after freezing.During the freezing process,the relatively stable g-g-g configuration was transformed to unstable gauche-gauche-trans(g-g-t)and trans-gauche-trans(t-g-t)configuration.The ratio between the intensities of the absorption peaks at 740 and 1004 cm^(-1)(I_(740/1004))in the Raman spectrum,which represents the microenvironment around the side chains of amino acids,reached the maximum when 45%water was added to dough,and decreased continuously during freezing.At the end of freeze,there was no significant difference in the relative percentage ofα-helix in the secondary structure of gluten proteins with water addition,but the relative percentage ofα-helix decreased by 3.63%during the freezing process.The results of water distribution and migration showed that the quality deterioration caused by ice crystal growth appeared earlier with the increase of water addition during the freezing process of dough.The results of this study will help to clarify the mechanism of dough quality deterioration during freezing.
作者
张华
张普
张予涵
刘兴丽
张艳艳
ZHANG Hua;ZHANG Pu;ZHANG Yuhan;LIU Xingli;ZHANG Yanyan(Collaborative Innovation Center of Food Production and Safety,Henan Province,Henan Key Laboratory of Cold Chain Food Qualify and Safety Control,College of Food and Bioengineering,Zhengzhou University of Light Industry,Zhengzhou 450000,China)
出处
《食品科学》
EI
CAS
CSCD
北大核心
2023年第2期39-44,共6页
Food Science
基金
国家自然科学基金河南联合基金项目(U200410718)。
关键词
冷冻面团
面筋蛋白
分子结构
水分分布
frozen dough
gluten
molecular structure
moisture distribution
