Effects Of Different Treatments On The Physicochemical Propertifs Of Wheat Bran

Wheat bran,as a by-product produced during the processing of wheat,contains high quality dietary fiber and active substances,but due to its poor processing adaptability and rough taste,it is difficult for consumers to accept.Therefore,it is of great significance to study a processing method that can improve the taste and processing characteristics of wheat bran and make full use of wheat bran to improve the processing efficiency of the product.In this paper,wheat bran was used as raw material,and the wheat bran was pretreated by extrusion,steam explosion and enzymolysis.The different processing methods and different wheat bran particle size were compared to the water holding capacity,expansibility and oil holding capacity.The effects of color,sodium cholate adsorption capacity and cation exchange capacity were analyzed.The effect of wheat bran processing method,addition amount and particle size on the gelatinization characteristics of wheat flour was analyzed by Brabender viscometer.The main results are as follows:Based on the crushing efficiency of the processed wheat bran,the optimum extrusion process is determined as follows:moisture content 40%,screw speed 120 r/min,extrusion temperature 1 zone 120?,zone 2 120?,zone 3 140?,4 zones,160?;The optimum steam explosion treatment process is as follows:pressure holding time 5 min,solid-liquid ratio 1:0.7(g/mL),steam pressure 0.8 MPa;the optimum process for enzymolysis treatment is:The total amount of enzyme added was 0.3%of the quality of wheat bran,the ratio of solid to liquid was 1:10(g/mL),the ratio of cellulase to xylanase was 1:2,the enzymolysis temperature was 550C,and the enzymolysis time was 5 h,the enzymolysis pH is 4.5.The water holding capacity,swelling force,oil holding capacity,sodium choline adsorption capacity and cation exchange capacity of wheat bran decreased with the decrease of the particle size of wheat bran.Extrusion,steam explosion,and enzymatic treatment all increase the water holding capacity,swelling force and oil holding power of wheat bran.Among them,when the particle size is in the range of 150-178 ?m,the water holding capacity of the wheat bran raw material by the extrusion treatment is the most significant(p<0.05),which is 12.97%.When the particle size is in the range of 250-420 ?m,the swelling power of the wheat bran raw material by the extrusion treatment increases most significantly(p<0.05),which is 68.27%;oil holding capacity of the wheat bran raw material is most significantly increased by the enzymolysis treatment(p<0.05).It is 31.81%.Extrusion,steam explosion,and enzymolysis treatment decreased the sodium cholate adsorption capacity and cation exchange capacity of wheat bran.The degradation of phytate by extrusion and steam explosion treatment was significantly stronger than that by enzymolysis treatment.Compared with the untreated wheat bran,the wheat bran added with extrusion,steam explosion and enzymolysis treatment had a significantly weaker effect on the characteristics of wheat flour viscosity(p<0.05).The enzymatic hydrolysis of wheat bran decreased the peak viscosity,final viscosity and retrogradation value of wheat flour(p<0.05),and increased by 11.02%,9.88%and 9.69%,respectively.The start time and gelatinization temperature of the wheat flour-wheat bran mixed system increased with the increase of wheat bran addition,and the peak viscosity,final viscosity and retrogradation value decreased with the increase of wheat bran addition.In the range of 150-420 ?m particle size,the peak viscosity,final viscosity and setback values of low-gluten,medium-strength,and high-gluten wheat flours are consistent with the grain size of wheat,wheat,wheat,and wheat bran,respectively.The trend of decreasing first and then increasing,while the start time and gelatinization temperature of the wheat flour-wheat bran mixture decreased with the decrease of the wheat bran particle size.Within different particle size ranges,the wheat bran The processing method also had a significant influence on the gelatinization index of the wheat flour-wheat bran mixed system(p<0.05).