Study On The Effects Of Wheat Bran Dietary Fiber On Noodle Quality

Dietary fiber as"the seventh nutrient"in improving the health level of the role of being seriously,and wheat bran is the main by-product in the process of wheat flour production as an excellent source of dietary fiber.Therefore,wheat bran dietary fiber（WBDF）was added to noodles that can supplement the dietary fiber intake required by human body in daily diet.Due to the characteristics of WBDF,it will affect the quality of noodles.The effects of different addition of WBDF on the rheological properties,protein properties and starch properties of stage products in noodle processing,and carried out correlation analysis with cooked noodle quality were studied in order to explore the effects of WBDF on noodles quality.Firstly,the effects of different addition of WBDF on the microstructures,cooking qualities,texture characteristics and sensory evaluation of noodles were studied.The microstructures of noodles were observed by scanning electron microscopy（SEM）.With the increase of WBDF addition,the tight gluten network structure of noodles was destroyed and starch particles were escaped.The correlation analysis results of WBDF addition and cooking qualities,textural characteristics and sensory score of noodles showed that there was a significantly negative correlation between noodle qualities and WBDF addition.Secondly,the results of the study on the effects of WBDF addition on the rheological properties of noodle stage products showed that the increased content of small dough crumbs and the decreased content of large dough crumbs,the decreased T₂,the increased A₂₁and A₂₂which the latter is greater than the former,the increased hardness and the decreased cohesion and elasticity of dough crumbs and sheeted dough,the increased G’and G",the decreased maximum creep variable,with the increase of WBDF addition.The content of strongly bound water of dough crumbs and sheeted dough were increased,while G’and G"were decreased with curing and calendering.According to the results of correlation analysis,the qualities of noodles are significantly positive correlation with the content of large dough crumbs,A₂₁and maximum creep variable,but negative correlation with the hardness,G’and G"of dough crumbs and sheeted dough.The microstructure of the sheeted dough showed that the high addition amount（>4%）of WBDF can destroy the structure of gluten network,but the maturation can improve the quality of the sheeted dough to a certain extent.Finally,the results of the study on the protein properties of noodle stage products showed that the significantly decreased content of GMP,the decreased content ofβ-turn,α-helix,LPP and SPP,while the increased content of free sulfhydryl group,β-fold and LMP,with the increase of WBDF addition.The content of free sulfhydryl group were reduced by curing,but the effect of calendering is opposite.And the content ofβ-turn andα-helix structure were increased by curing.The content of LPP and SPP were increased while the decreased content of LMP by curing and calendering with 2%concentration of WBDF addition,but the effect is opposite with continued increased concentration of WBDF addition.The results of correlation analysis showed that the contents of GMP,α-helix andβ-turn,LPP and SPP were negatively correlated with cooking characteristics,hardness and adhesion of noodles,and were positively correlated with cohesion,elasticity,chewiness and tensile properties of noodles,and were positively correlated with sensory score.The content of free sulfhydryl group,β-fold and random coil,LMP and SMP were negatively correlated with the quality of noodles.The effects of WBDF on starch properties of noodle stage products showed that the gelatinization indexes of noodle stage products,such as peak viscosity,trough viscosity and final viscosity were significantly reduced.The hardness,adhesion,cohesion and rupture strength of the gel were decreased,while its elasticity was increased.T_oand△H of starch were increased trend in dough crumbs.T_owas increased gradually and△H was decreased in sheeted dough.The results of correlation analysis showed that noodle quality was positively correlated with peak viscosity and setback value of pasting starch,hardness,adhesion and rupture strength of starch gel,and negatively correlated with breakdown value and T_oof starch.In this paper,the effect of WBDF（mainly insoluble dietary fiber）on the rheological properties,protein properties and starch properties of noodles and noodles in the process of noodle processing was studied,and the correlation analysis was carried out with the quality of noodles.The influence of the modified dietary fiber of wheat bran on noodle processing can be studied in the future,and appropriate addition amount can be obtained so that the better application of WBDF to product dietary noodles.