青麦粉添加对馒头面团及面筋蛋白结构的影响

Effect of Adding Green Wheat Flour on the Dough of Steamed Bread and Structure of Its Gluten Protein

摘要:

以馒头专用粉及青麦粉制作青麦馒头，利用激光共聚焦显微镜、黏度仪、红外光谱仪等分析仪器进行测定，探究不同青麦粉添加量（0%、5%、10%、15%、20%）对面团粉质特性、糊化特性、微观结构及面筋蛋白二级结构的影响。结果表明，随着青麦粉添加量的增加，混合粉湿面筋含量、面筋指数减少；糊化温度、峰值黏度降低，面团糊化时间缩短，面团稳定时间从6.18 min降至4.92 min、粉质质量指数减小了18，面筋强度变弱，承受力变差；面团拉伸面积、延伸度和最大拉伸阻力在135 min时显著减小；面筋网络结构逐渐出现孔洞，分布不均匀；面团面筋蛋白各吸收峰都发生了偏移，β-折叠和α-螺旋结构含量增加；综上所述，青麦粉的加入改变了面团特性和面筋蛋白结构，这些变化可能是导致青麦馒头品质下降的主要原因。

Abstract:

Steamed bread was made using steamed bread specialized flourr and green wheat flour. Analytical instruments such as laser confocal microscope and rapid visco analyser (RVA) and fourier transform infrared (FT-IR) spectroscopy were used to examine the impacts of adding green wheat flour in different amounts (0%~20%) on the characteristics of bread dough, gelatinization properties, microstructure and gluten protein secondary structure. The results showed that the increase of the amount of green wheat flour caused decreased wet gluten content and gluten index, reduced pasting temperature and peak viscosity, shortened gelatinization processing time, decreased dough stability time (from 6.18 to 4.92 min), reduced flour quality index (by 18), weakened gluten strength and tolerance, reduced tensile area, elasticity, maximum tensile resistance of dough at the 135th min, gradual appearance and uneven distribution of voids in the gluten network structure , and shift of individual absorption peaks of gluten protein, and increased beta-sheet and alpha-helical structure contents. In summary, addition of green wheat flour could change dough properties and gluten structure, which may be the main cause of decreased final product quality.