The effects of oat bran addition amount on the dough rheological properties and gluten structures

To investigate the effects of oat bran on dough and gluten quality characteristics,the substitution of oat bran was 0%,10%,15%,20%,25%(w/w). The results showed that with the increasing amount of oat bran added,water absorption,formation time and breakdown viscosity of the dough were significantly increased(p<0.05),and the stability time,setback value were significantly decreased(p<0.05),which suggested the thermomechanical properties of the dough were decreased. The elastic modulus and the viscous modulus of gluten were increased,while the tan δ value was decreased,which indicated the solid properties and mechanical strength of gluten were increased by adding oat bran. The thermostability of gluten were decreased as the degradation temperature of gluten were significantly decreased(p<0.05)and the weight loss at 600 ℃ of gluten were significantly increased(p<0.05)along with the increasing amount of oat bran. The disulfide bonds content of gluten were significantly decreased 25.74%~37.58%. The results of scanning electron microscopy showed that addition of oat bran destroyed the smoothest and uniform of the gluten network,resulting in the formation of a weaker and flaky with jagged edges gluten network. In conclusion,addition of oat bran could destroy the gluten protein network structures and this might lead the deterioration of rheological properties of the dough.