Abstract: 【Objective】 Mechanism and effect of bran addition and particle size on mixing properties of dough were analyzed to provide a scientific basis for application of wheat bran in food production. 【Method】 Aiming to study the effects of wheat bran addition level and particle size on the mixing property of wheat flour, wheat bran produced from Shannong 2 were added into flour, with bran addition of 5%, 10%, 15%, 20% and with bran particle size of 0.16-0.43 mm, 0.43-1.0 mm, 1.5-2.0 mm and 2.0-2.5 mm. The mixing properties of the mixed flour samples were determined. 【Result】 With the increasing addition level of wheat bran the midline peak value, midline peak width, 8 min value and integral, curve tail value and integral decreased significantly, while the 8 min width, curve width and slope of peak right increased remarkably. There was no remarkable difference in effects of bran addition levels on midline peak time, peak time integral and slope of peak left. With the increasing particle size the midline peak time, 8 min width, curve tail width and slope of peak right increased significantly, but no remarkable different effects were detected in other mixing parameters. 【Conclusion】 Wheat bran decreased significantly the midline peak value，8 min midline value, peak time integral and 8 min midline integral, while increased the midline peak time and 8 min width and slope of right of peak. With the increasing particle size the midline peak time, 8 min width, curve tail width and slope of peak right increased significantly.

Key words: wheat, bran, mixing proprieties, particle size