氯化钠对小麦特二粉面筋聚集特性的影响

Effect of sodium chloride on the aggregation characteristics of second-grade wheat flour

为探究氯化钠改良小麦面团特性的机理,以小麦特二粉为材料,利用面筋聚集仪等仪器分析了氯化钠质量浓度对面筋聚集过程中峰值时间(PMT)、峰值扭矩(BEM)、启动能量(S_(1))、稳定能量(S_(2))和聚集能量(S_(3))的影响,以及对湿面筋含量、蛋白质提取量和面筋显微结构的影响。结果表明:随氯化钠质量浓度增加PMT呈直线上升趋势,氯化钠的添加延长了面筋聚合时间,降低了面筋聚集速度;氯化钠质量浓度对BEM影响不显著,说明氯化钠的添加对面筋蛋白网络结构的强化不显著;随着氯化钠质量浓度的增加,S_(1)未有显著增加,而S_(2)和S_(3)增加显著;在面筋聚集过程中,添加氯化钠减少了洗出的湿面筋量,却增加了面筋蛋白网络的韧性;氯化钠使提取的水溶蛋白、盐溶蛋白和醇溶蛋白含量的变化不稳定,但可使面筋网格结构更加均匀,面筋蛋白更好地包裹淀粉颗粒,有效降低了淀粉颗粒的破碎。氯化钠改变了小麦面团的面筋网络形成进而影响其面筋的聚集特性。

To explore the mechanism of sodium chloride on improving the characteristics of wheat dough,the effects of sodium chloride mass concentration on peak maximum time(PMT),brabender equivalents maximum(BEM),starting energy(S_(1)),stable energy(S_(2))and accumulation energy(S_(3))in the process of gluten aggregation were analyzed by using wheat special powder as the material,and the effects on wet gluten content,protein extraction and gluten microstructure were analyzed.The results showed that the mass concentration of sodium chloride and PMT value showed a straight apuard trend,and the addition of sodium chloride prolonged the gluten polymerization time and reduced the gluten aggregation rate.The effect on BEM value was not significant,indicating that sodium chloride addition did not significantly strengthen the network structure of gluten protein.With the increase of sodium chloride concentration,S_(1)did not increase significantly,while S_(2)and S_(3)increased significantly.In the process of gluten aggregation,sodium chloride could reduce the amount of wet gluten washed out,while increased the toughness of the gluten protein network.Although sodium chloride changed extracted hydrolytic protein,made hydrolytic protein and gliadin unstable,the gluten grid structure was more uniform,and the gluten protein better wrapped the starch granules,which effectively reduced the fragmentation of starch granules.Therefore,sodium chloride changed the formation of the gluten network of wheat dough,which in turn affected its gluten aggregation characteristics.