Extrusion Of Oat Bran Modification Process Optimization And Efficacy Study

Oat dietary fiber which can lower blood sugar, blood cholesterol and enhance theimmune system has attracted much attention, in which β-glucan being a water-soluble dietaryfiber plays a major effect. Oat bran being rich in oat dietary fiber, protein and some effectiveingredients is a good resource for oat dietary fiber and oat protein. Therefore to study the oatbran modified for more efficient access to high quality oat dietary fiber and oat protein isgreat significance. Oat bran as raw material was modified by extrusion technology optimizedby response surface methodology. Oat bran modified efficacy studies by animal experiments.The main results are as follows:1、Oat bran extrusion modification process was optimized by a single factor experimentand response surface methodology. The parameters of the process of extraction of oatβ-glucan were as follows: extrusion temperature142°C, screw speed9rad/min, bran moisturecontent47%, and citric acid content1.2%. Under these conditions, forecast the rate of oatβ-glucan was136.95mg/g. Extract of oat protein process parameters for the extrusionprocessing were as: extrusion temperature199°C, screw speed7rad/min, the moisture content59%, citric acid content1.3%. In these conditions, protein extract rat was13.51mg/g by theregression model prediction.2、Extrusion modified oat bran was analyzed by scanning electron microscopy andFourier transform infrared spectroscopy. The results showed that: the microscopic structure ofthe oat bran after extrusion changes significantly, oat bran particles dispersed and internal wassmooth before extrusion; Oat bran after extrusion was dispersed granular, dense structure andwith the obvious layering. Extruded oat bran does not generate a new amide bond.3、Oat bran β-glucan molecular weight was measured by GPC to compare before andafter extrusion. The average molecular weight of first oat bran β-glucan was1.075×106, andthe after one increased was2.230×106.4、Extrusion of the modified oat proteins were analyzed by SDS-PAGE, isoelectric pointand amino acid composition. The results showed that: protein molecular weight was no majorchanges and there was no new subunit generated; protein isoelectricpoint was reduced to3.5after modified; amino acids was loosed in varying degrees, the most loss was methionineloosed16.2%.5、The efficacy of modified oat bran was studied by animal experiments. The resultsshowed that: the modified oat bran can significantly lower blood glucose, serum cholesterol and triglyceride and can reduce pH values in the intestinal and inhibit the growth of E. coli, toincrease the number of probiotic lactic acid bacteria and bifidobacteria in the intestinal.