Abstract:In order to investigate the effect on the dough and bread quality of wheat and sweet potato powder，wheat flour was replaced by different proportions（0%-50%）of sweet potato whole flour to prepare steamed bread，and the quality of sweet potato whole flour on wheat dough and steamed bread was studied by using rotary rheometer，rheology fermentation instrument，starch gelatinizer and texture analyzer.The results showed that with the increase of sweet potato whole flour content，the elasticity modulus and viscosity modulus of the dough increased，and the tanδ decreased gradually.The maximum expansion height and dough holding rate of the dough decreased significantly，and the maximum height of gas release curve and the total gas production of CO2 increased significantly.Compared with the control group，the pasting characteristic curve of the dough decreased significantly after the addition of sweet potato whole flour，and the peak viscosity，falling value and rebound value of the mixed powder decreased.The addition of sweet potato whole flour gradually increases the hardness，adhesiveness and chewiness of the steamed bread，and the elasticity and recovery were significantly reduced.At the same time，the specific volume of the steamed bread was reduced and the brightness was darkened.Laser scanning confocal microscopy results showed that the addition of sweet potato whole flour hinders the formation of the gluten network structure.