Effects Of Micronization And Dry Method Gelatinization On Physicochemical Properties Of Oat Flour And Processing Quality Of Oat Dough

Due to the lack of wheat gluten and rich in cellulose, no matter processed oat into oat flour or oatmeal there still exist the problem of palatability. In this thesis, mechanical crushing and dry method gelatinization were used to improve the taste of oat, and then studied the effects of granularity and gelatinization degree on the quality of oat flour and dough.The results show that the longer grinding time the smaller average particle diameter D [4,3], and the less content of amylose,at the same time the content of damaged starch, gelatinization degree and the dissolution of beta glucan had been increased; the results of DSC parameters of oat starch showed that: the change of Tp is irregular, △H showed a trend of increase; DSC parameters of oat Protein: Tp changed between106.05~107.8 ℃ and no significant difference(P < 0.05), Tc-T0 and △H all showed a trend of decrease; There was no addition or missing in the band of SDS-PAGE electrophores of oat protein.After dry paste treatment, the gelatinization degree of oat flour have changed in different degrees. The gelatinization degree of oat flour dealed with extrusion processing was closed to 80%, the other three kinds of treatment were no more than 40%. The research of TPA of oat dough though Extrusion processing and steam treatment showed a larger hardness,adhesion and cohesion. Among the five kinds of processing, the effect on the texture of the dough, microwave treatment is in between, and untreated processing and baking processing are least, but all of them were significantly higher than that of wheat flour; With the increasing of water content, the hardness and adhesion of the dough treated with five dry methods and the wheat flour dough were reduced, but the cohesion were increased; Stress relaxation characteristics show that among the four kinds of dry paste, gelatinization degree,viscosity and internal bond strength of oat dough treated by extrusion processing were maximum and easy to form a dough,hence the extrusion is suitable method for dry paste on oatmeal.With the decrease of the granularity, the water absorption of oat flour was increased gradually, the more uniform of the quality of forming the dough, the smaller particles of the dough, and the greater the hardness and adhesion, but the smaller of the cohesion. when the granularity under the same distribution and the more content of moisture, the hardness of the dough was greater, the cohesion was smaller and had a significant difference at the same time, the adhesion decreased gradually and the difference was not significant.When the particle size of D[4,3] was 73.64 μm and the gelatinization degree was 70%, the hardness, adhesion, cohesionoat of oat dough were optima.When the ratio of Raw powder and gelatinization powder with wheat flour were 6:4 respectively, the texture of oat dough were optimal and was suitable for making staple food of noodles. The sensory score of the noodles making with Gelatinization wheat powder was the most close to the wheat flour noodles, and the sensory score of raw powder wheat flour noodles was the worst.The results in this research showed that particle size can influence the physical quality of oatmeal, and as well as improved the processing quality of oat dough, make it easy to form a smooth dough in cold water. Dry method could improve the quality of dough by changing the gelatinization degree of oat flour; extrusion processing could improve oat flour gelatinization degree to a great extent, which can be as experimental treatment of choice for subsequent staple food.