微波和超声处理对麦麸研磨特性及全麦面团品质的影响

麦麸经过微波与超声处理后，研磨筛分成粗（280~450 μm）、中（154~180 μm）、细（≤71 μm）三种粒径，再将不同粒径麦麸回添至面粉中制成全麦面团，以此探究微波和超声处理以及不同粒径对全麦面团的全质构、动态流变学性质以及游离巯基的影响。麦麸的相对酶活与粒径分布表明，超声处理和微波处理均能较好提升稳定化效果和粉碎效率，且超声处理组的效果更好（P<0.05）。面团的品质显示，随麦麸粒径减小，微波处理组的硬度和胶黏性呈现下降趋势，内聚性呈现上升的趋势，超声处理组的硬度和胶黏性均小于微波处理组（P<0.05）；微波组弹性模量和黏性模量随着麦麸的粒径减小而减小，同种粒径时，超声处理组弹性模量和黏性模量均小于微波处理组；随麦麸粒径减小，各处理组的游离巯基含量逐渐降低，且超声处理组的游离巯基含量降低幅度大于微波处理组（P<0.05）。微波与超声处理及麦麸粒径的减小均能有效改善面团的品质，且超声处理的麦麸对面团品质影响相比微波组更显著。

Effects of Microwave and Ultrasound Treatment on the Grinding Characteristics of Wheat Bran and the Quality of Whole Wheat Dough

After treated by microwave and ultrasound, the wheat bran was ground and sieved into three parts, coarse (280~450 μm), medium (154~180 μm) and fine (≤71 μm). Then the texture properties, rheological properties and free sulfhydryl content of whole-wheat dough were investigated. The relative enzyme activity and particle size distribution of wheat bran showed that ultrasonic treatment and microwave treatment could better improve the stabilization effect and crushing efficiency, and the effect of ultrasonic treatment group was better (P<0.05). The dough quality showed that with the decreasing of wheat bran particle size, the hardness and stickiness of microwave treatment group decreased, and the cohesion increased. The hardness and adhesiveness of ultrasonic treatment group were lower than those of microwave treatment group (P<0.05). Rheological analysis indicated that the elastic modulus and viscous modulus of the microwave group decreased as the particle size of bran decreased, and were smaller than those of ultrasound-treated group the microwave-treated group at the same particle size. The free sulfhydryl content decreased gradually with the decreasing of bran particle size, and the decreasing of free sulfhydryl content was greater in the ultrasonic treatment (P<0.05). Microwave, ultrasonic treatment and the reduction of wheat bran particle size could effectively improve the quality of dough. In addition, the effect of ultrasonic treatment on dough quality was more significant than that of the microwave treatment group.