茶多酚对面团中面筋蛋白结构的影响

Effect of Tea Polyphenols on the Structural Property of Gluten in Wheat Dough

本研究通过对面团面筋中自由氨基和二硫键含量的检测,并采用拉曼光谱和扫描电镜对面团结构的分析,探究茶多酚对面筋蛋白结构的影响。结果表明,茶多酚在面团中添加量为0.5%、1.0%、2.0%时,面团中湿面筋的含量分别降低了17.8%、66.3%和93.3%;游离氨基含量分别增加了57%、151%和313%;自由巯基含量分别增加了48%、69%、111%。拉曼光谱分析表明茶多酚的添加使得面团中的氢键作用有所增强;蛋白质二级结构的分析表明,2.0%的茶多酚降低了α-螺旋的相对含量(21.9%),而β-折叠和无规则卷曲结构则分别增加了17.2%和5.1%;随着茶多酚添加量的增加,色氨酸残基I_(757)相对强度逐渐降低,并且二硫键的扭-扭-反结构分别增加了3.0%、6.0%、13.4%。综上所述,茶多酚的添加破坏了面筋蛋白网络结构,与扫描电镜和激光共聚焦显微镜的结果一致。因此,防止茶多酚与面筋蛋白的相互作用是开发含有多酚类功能性面制品的基础。

The effect of tea polyphenols on the structural property of gluten in the wheat dough was analyzed by Raman spectroscopy and scanning electron microscopy(SEM).With 0.5%,1.0%,2.0%of tea polyphenols addition,the content of wet gluten in the dough decreased by 17.8%,66.3%and 93.3%,the free amino content increased by 57%,151%and 313%,and the content of sulfhydryl increased by 48%,69%and 111%,respectively.Raman spectroscopy analysis showed that the addition of tea polyphenols led to an increasing in hydrogen bonding of dough,the relative content ofα-helix(21.9%)reduced,and theβ-sheet and random coil secondary structure increased by 17.2%and 5.1%,and dose-dependently reduced the relative absorption intensity of tryptophan residue at 757 cm-1.Additionally,the analysis of the conformation of disulfide bonds showed that they were transformed from gauche-gauche-gauche to gauche-gauche-trans with an increase rate of 3.0%,6.0%,13.4%along the content of tea polyphenols addition of 0.5%,1.0%to 2.0%.SEM and CSLM analysis revealed a disrupted gluten network structure.Thus,preventing the interaction of tea polyphenols with gluten is essential for the development of the functional dough-based food containing flavonoids.