Quality Improvement and Structural Characteristics of Wheat Bran by Microwave Enzymatic Method

Using wheat bran as raw material,orthogonal experiment was used to optimize the technological parameters of microwave combined enzymatic hydrolysis to improve the quality of wheat bran,and the effects of microwave,enzymatic hydrolysis and microwave combined enzymatic hydrolysis on the structure and properties of wheat bran were analyzed.The study found that,wheat bran microwave combined enzymatic hydrolysis of the optimal technological parameters were:microwave power 700 W,time 15 min,ratio of material to water 1:4,xylanase added amount 0.4 g,cellulase added amount 0.4 g,enzymatic hydrolysis time 4 h,enzymatic hydrolysis temperature 60 ℃,at this time the reducing sugar content in wheat bran was 25.15 mg/mL.After microwave enzymolysis,water holding capacity of wheat bran increased by 30.18%,phytic acid content decreased by 70.46%,oil holding capacity decreased by 26.69%,lipase(LA)residual enzyme activity decreased to 6.13%,crude fiber content decreased to 2.79%,and reducing sugar content increased to 25.15 mg/mL.The results of FTIR showed that microwave enzymatic hydrolysis could break the glycoside bonds between the molecules,degrade cellulose and hemicellulose in the cell wall of wheat bran,and produce small reducing sugars.The results of scanning electron microscope showed that microwave combined with enzymatic hydrolysis destroyed the structure of wheat bran,making the surface of wheat bran rough,loose and porous.The lipase residual activity in modified wheat bran was significantly decreased and the edible quality of wheat bran was significantly improved.