|
Of soybean-producing countries and consuming countries, the many soy process will generate a lot of bean dregs, most of which have not been good development and utilization, only used as feed or fuel, even as garbage discarded directly, not only low, and caused a great deal of pollution on the environment. Bean dregs as raw material, the study was to investigate the of bean dregs of insoluble dietary fiber modification process and its physical and chemical characteristics, and provide a theoretical basis for bean dregs comprehensive utilization of resources and guiding role. The results are as follows: 1, a modified process to determine: Okara insoluble dietary fiber modified by chemical methods, the water holding capacity as the marker. The first screening of modified reagents, and then single factor experiments, and finally by orthogonal design process optimization test. The experimental results show that: the optimum conditions of the modification process: disodium hydrogen phosphate solution concentration of 0.1%, solid-liquid ratio of 1:60, the processing time of 1h, the processing temperature of 50 ° C for 2 significantly improve the hydration characteristics of the modified dietary fiber. After modification, the water holding capacity of insoluble bean dregs dietary fiber 11.95 g / g the expansion force 17.90ml / g, combined with hydraulic 3.40 g / g, the oil holding force of 4.35 g / g, compared with pre-modified to varying degrees the improvement, so that the Physiological Functions of dietary fiber is enhanced. Modified dietary fiber adsorption capacity of the NO2-: modified dietary fiber under different pH conditions of 37 ° C when the NO2-adsorption capacity is higher, but decreases with the increase of pH the PH2 when 56umol / g, The pH3 when 53umol / g the PH5 when 40umol / g, pH7 34umol / g. 4, a modified dietary fiber has a strong adsorption capacity of the metal, studies show that for Pb2 ??Cu2, Zn2, Fe3, Mg2, Ca2 adsorption capacity were 0.524 mmol / g, 0.456 mmol / g, 0.040 mMol / g, 0.019 mmol / g, 0.190mmol / g, 0.303mmol / g. 5, the structural characteristics of the modified dietary fiber: ① modified dietary fiber and to share the basic structure of dietary fiber having a high degree of consistency. This is mainly reflected in the high degree of similarity of the two infrared spectroscopy, they have polysaccharide characteristic absorption peak at 1000-1100 cm-1 has a phosphate group. (2) X-ray diffraction showed that the the modified reagents may cause a decline in dietary fiber crystallinity and degree of polymerization, the product structure is more loose, but limited impact on the structure from the numerical point of view of the degree of crystallinity changes. 3 DSC curve of the difference modified dietary fiber than the commercially available dietary fiber content is a single, high purity, and a stronger ability to adsorb water. ④ scanning electron microscope observation showed that the modified dietary fiber particles than commercially share the finer particles of a dietary fiber, slightly wrinkled surface, loose structure, with a clear sheet-like structure, the particle surface of the honeycomb structure, and the distribution is uniform. In summary, the X-ray diffraction, DSC curve measured, the scanning electron microscope are shown as a modifying reagent disodium hydrogenphosphate, under the process conditions, the structure of the soybean dietary fibers play a certain role in modified. Be effective in improving the hydration properties and adsorption properties of the modified dietary fiber, can predict the physiological function and food processing characteristics will further improve. Therefore, this study modified insoluble bean dregs dietary fiber has good development prospects, and the process is simple, low cost, has a larger development value.
|