| As healthy wheat bran bread is,it is cannot be more popular because it is smaller,harder and of more coarse crumb than white bread.The paper was aimed at improving baking quality of bran bread by additives.In addition,it studied the effect of cellulase and fungle xylanase on diatary fibre from wheat bran to investigate why they could improve bran bread quality.After single factor tests and orthogonal experiments, fungleα-amylase, fungle xylanase,cellulase and glucose oxidase were chosen to mix as enzyme additives for bran bread. The best ratio was 5:5:6:7.It was found that the enzyme prepare could enlarge volume of bran bread by 20.4 percent and improve the crumb texture .Further more the bread added with mixed enzymes tasted better and staled slower.After single factor tests and orthogonal experiments, SSL, DATEM and SMG were chosen to mix as emulsifier additives for bran bread. The best ratio was 3:4:6. DATEM was good at enlarging the volume, however it was not so successful in slowing bread staling. Relatively, SSL and SMG acted a full effect.The emulsifier mixture could improve the dough mechanical quality and baking quality.Based on the chosen enzymes and emulsifiers,the final recipe of compound additives was got by adding ascorbic acid.The most efficient ratio was enzyme mixture 0.8%,emulsifier mixture 80%, ascorbic acid 0.4% and bulking agent 18.8%.The recipe could enlarge the volume by 30.2%.The bread became more soft and delicious.By studying the change of distribution of SDF relative molecule weight, infrared spectrum of IDF and diatary bran fibre composition and physical characteristics after adding fungle xylanase or/and cellulase, the result showed the synergetic effect.They hydrolyze cell wall,converting the unsoluble non-starch polysaccharide to water soluble components and water soluble non-starch polysaccharides of large relative molecule weight to smallar ones.As a result the baking quality and physiological function of bran bread were improved.
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