The Research Of Producting Dietary Fiber From Wheat Bran Using Multi-enzyme Step-by-step

The extraction and physicochemical properties of dietary fiber were studied in this dissertation, using wheat bran which was the byproduct of milling as raw material,also the application of the dietary fiber in the products was researched and the pilot production line of 100 kg/day of wheat bran dietary fiber was designed according to preparation process. The main results are as follows:multi-enzyme step-by-step was considered as the optimal method in the extraction of dietary fiber from the wheat bran though the comparing the method of alkali, single enzyme , and multi-enzyme step-by-step;The parameter of the process is:α-amylase 0.5%, lipase 0.1%, neutral 0.2%. the treatment of temperature in the step respectively were: 100℃,40-42℃,35℃,all hydrolysis in the constant temperature for 45 minutes.The best method of decolourization as follows: the ratio of H₂O₂ and NaClO is1:3, in accordance with solid-liquid mixture's 30% and 60 minutes.The results of physicochemical properties of dietary fiber shows that when the size was less than 100μm,the net structure was destroyed, the distensibility, swell decreased and buoyancy increased evidently, when the size was less than 70μm, the time of buoyancy could reach 60min. we can choose reasonable fineness by the different uses of wheat bran dietary fiber.The using of dietary fiber of wheat bran influenced on the quality of flour,it shows that wheat bran dietary fiber can influence the formation of gluten network. With the addition increasing, this undermining is more obvious. Through the products experiments show that the addition wheat bran dietary fiber can obviously reduce the sensory and food quality of steamed bread and noodles.The suggested wheat bran dietary fiber contents can not beyond 2%.In order to achieve industrial production of wheat bran dietary fiber.the industrial production of wheat bran dietary fiber's technology was demonstrated. it gives the material balance to the production line: the daily production of 2 batches, each batch of raw material handling capacity 95.8 kg; the model of the equipment are: cleaning tank diameter 1.2 m, high 1.3 m, the volume 1.17 m³ ; Fermenter diameter of 1.1 m, high 1.5 m, volume of 1.233 m³; SS1000-type centrifuge, the effective volume of 140 L, centrifugal time 4～5min; SKG100 Cyclones dryer, evaporation 100 kg/h; WFJ-15 disintegrator, the capacity 10～200kg/h. Mechanization and reliable technology, reasonable layout of the production process should be fully took into account.