| The decoloration, micronization and application of wheat bran dietary were studied in this paper. Mixed Enzymatic Method was used to extract Dietary fiber form Wheat bran. Peroxide hydrogen was chosen as the decoloring agent.Result showed that optimum decoloration condition of peroxide hydrogen and microwave assistant decolored was 6% decoloring agent concentration, pH9, decoloring time was 120s and power was 800W. Finally the L could reach to 86.67, 31.59 higher than before. The effect was obvious. After decoloration the content of protein and starch was reduced in the dietary fiber, the content of IDF was enhanced to 82.13%, and color was improved.DF was crushed by vibratory crusher, and granule size of dietary fiber were changed from hundreds um to 20-30um after crushed. The content of SDF and the L were improved effectly, enhanced by 7.37 and 3.29 respectively. The RW, WRC, ORC and the adsorption of cholesterol of dietary fiber were improved after decoloration, but the adsorption of heavy metal ion and the Cation-exchange capacity were falled. However, the RW, WRC, ORC and the adsorption of cholesterol of dietary fiber were falled after micronization, but the adsorption of heavy metal ion and the Cation-exchange capacity were improved. The effect to antioxidant activities of high fibre products from wheat bran by decoloration and micronization were studied by the vitro methods. The DPPH? scavenging, reducing power and chelating ability were evaluated. The result showed that the of which dietary fibre (DF1) concentrates obtained from wheat bran withα-amylase and alcalase resulted in obvious losses of extractable phenolic (from 1239 to 379μg gallic acid equivalents/g) and the scavenging capacity on DPPH?, reducing power and chelating ability. The decoloration resulted in obvious losses of extractable phenolic (from 379 to 75μg gallic acid equivalents/g) and the scavenging capacity on DPPH? (from 17.11 to 4.09%), reducing power(from 0.146 to 0.052) and chelating ability(from 83.87 to 48.02%). While the next micronization resulted in obvious rise of extractable phenolic (from 75 to 403μg gallic acid equivalents/g) and the scavenging capacity on DPPH? (from 4.09 to 25.69%), reducing power(from 0.052 to 0.256) and chelating ability(from 48.02 to 81.23%). The picture of X-ray diffraction revealed that decoloration and micronization could not change crystal structure of DF. The picture of SEM showed that the ultrastracture of DF1 was small pieces, and the size of DF3 was minished rapidly.Influences of the dietary fiber (DF1 with none treatment and DF3 treated with decoloration and micronization) upon the rheology properties of wheat dough with medium-gluten flour were investigated by a Brabender farinograph and an Extensograph. The studies suggested that with the addition of dietary fiber increased, the rheology properties in dough was influenced. Both DF1 and DF3 improved the farinogram, but deteriorated the extensibility. Based on the comprehensive evaluation of farinogram and extensibility, the rheology properties were improved with the content of DF1 and DF3 in the low level (1%～3%).The influence on characteristics of sense, texture and color of steamed bread by DF1 and DF3 were also studied. The results showed that steamed bread made by 2% to 3% of DF1 was good in hardness, flexibility, chewiness and resilience, and the score of sense evaluation was favourable and the score was the highest when the DF1 content was 2%. When the content of DF1 was above 2%, the L was lower than 86, and the color was light brown, and the granule of DF1 could been seen clearly. Comprehensive evaluation of its content was 2%. The characteristics of texture of steamed bread made by less than 4% of DF3 was also good, and the score of sense evaluation was better than steamed bread made by DF1, and the score was the highest when the DF1 content was 3%. In the same accession, the L of DF3 was 93.72, 10.2 higher than DF1, and the color was lighter and better than DF1. Comprehensive evaluation of its content was 3%.
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