燕麦麸皮添加量对面团流变特性及面筋蛋白结构的影响

将燕麦麸皮以0%、10%、15%、20%、25%(w/w)的比例添加到小麦粉中,研究燕麦麸皮添加量对面团及面筋品质的影响。实验结果表明,随着燕麦麸皮添加量的增加,面团吸水率、形成时间、粘度崩解值显著(p<0.05)增加,稳定时间、回生值显著(p<0.05)降低,面团的热机械学性质下降;面筋蛋白的弹性模量、粘性模量增大,tan δ值降低,面筋蛋白固体特性增强,机械强度增大;面筋蛋白的热降解温度下降、600 ℃时的质量损失率显著(p<0.05)增大,面筋蛋白热稳定性降低;面筋蛋白二硫键含量显著(p<0.05)下降了25.74%~37.59%;扫描电镜的结果表明,添加燕麦麸皮后面筋蛋白原本均匀、致密的网络网络结构遭到破坏,面筋蛋白网络结构变得脆弱、呈蜂窝状。综上所述,添加燕麦麸皮会破坏面筋蛋白均匀致密的网络结构,这可能是导致面团流变性质劣变的原因。

The effects of oat bran addition amount on the dough rheological properties and gluten structures

To investigate the effects of oat bran on dough and gluten quality characteristics,the substitution of oat bran was 0%,10%,15%,20%,25%(w/w). The results showed that with the increasing amount of oat bran added,water absorption,formation time and breakdown viscosity of the dough were significantly increased(p<0.05),and the stability time,setback value were significantly decreased(p<0.05),which suggested the thermomechanical properties of the dough were decreased. The elastic modulus and the viscous modulus of gluten were increased,while the tan δ value was decreased,which indicated the solid properties and mechanical strength of gluten were increased by adding oat bran. The thermostability of gluten were decreased as the degradation temperature of gluten were significantly decreased(p<0.05)and the weight loss at 600 ℃ of gluten were significantly increased(p<0.05)along with the increasing amount of oat bran. The disulfide bonds content of gluten were significantly decreased 25.74%~37.58%. The results of scanning electron microscopy showed that addition of oat bran destroyed the smoothest and uniform of the gluten network,resulting in the formation of a weaker and flaky with jagged edges gluten network. In conclusion,addition of oat bran could destroy the gluten protein network structures and this might lead the deterioration of rheological properties of the dough.