Discussion on the Application of LS-DYNA in Superfine Grinding of Wheat Bran

Superfine grinding, involving the fragmentation mechanism of wheat bran cell tissue, is being employed by milling industry. In order to determine the effect of wheat bran cell tissue on the fragmentation mechanism when using superfine grinding,a technical scheme of the nonlinear finite element numerical simulation method based on LS-DYNA is proposed in this paper.The physiological characteristics of wheat bran structural layers including outer pericarp, intermediate layer and aleurone layer are examined first, and then the mechanical properties of wheat bran structural layers and their effects on the super fine grinding process are analyzed. Secondly, the explicit time integration algorithm of LS-DYNA is introduced, and the application feasibility of LS-DYNA in the analysis of wheat bran superfine grinding mechanism is discussed. Finally, the specific application of LS-DYNA in the determination of grinding form and load, the selection and design of the grinding media and the selection of grinding temperature are discussed in detail in the process of superfine grinding for wheat bran cell tissue. The above research provides a theoretical basis for selecting and developing the equipment and technology suitable for wheat bran superfine grinding, and lays a theoretical foundation for enhancing the quality and efficiency of wheat bran superfine grinding.

Effects of Wet Superfine Grinding on Polyphenols and Antioxidant Activities of Whole Fruit Pulp of Navel Orange

The navel orange were cleaned and pulverized by a wet superfine grinding and a broken wall cooking machine,then the navel orange whole fruit pulp were obtained by wet superfine grinding once,wet superfine grinding twice,and broken wall cooking machine processing.The particle size distribution,free polyphenols,bound polyphenols and antioxidant activity of whole fruit pulp prepared by the three kinds of pulverization methods were discussed.The results showed that the particle size distribution of the whole fruit pulp by wet superfine grinding was more concentrated compared with the broken-wall cooking machine processing,and the total phenols dissolution rate of the navel orange whole pulp was increased by 6.9%,and the total flavonoid dissolution rate was increased by 13.5%.The results also suggested that wet superfine grinding twice could improve 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radical scavenging activity of polyphenols in the whole fruit pulp,wet superfine grinding once and wet superfine grinding twice also could obviously enhance the reducing power and iron reduction ability of polyphenols in the whole fruit pulp.In conclusion,wet superfine grinding could increase both the polyphenol content and antioxidant activity of navel orange whole fruit pulp,it can be used as a pretreatment processing method for preparing navel orange whole fruit pulp.

Influences of four processing methods on main nutritional components of foxtail millet: A review

Foxtail millet, originated from China and now cultivated worldwide, is a kind of high dietary fiber whole grain food, and has a high level of vitamins and proteins. Furthermore, foxtail millet has many positive effects on the adjuvant treatment of diabetes, cancer, and cardiovascular diseases because of the abundance in polyphenols. Nonetheless, foxtail millet has poor processing characteristics due to the absence of gluten, restricting the development of foxtail millet products. Studies have demonstrated that heat-moisture treatment, extrusion, superfine grinding, and microbial fermentation are promising methods to improve the processing qualities of foxtail millet. Heat-moisture treatment is helpful to increase the content of resistant starch but has less influence on other components, further reduce the GI value of foxtail millet. The extrusion has positive effects on improving the solubility of foxtail millet starch and increasing the contents of polyunsaturated fatty acid, linoleic and linolenic acids, and adverse effects on reducing the solubility of foxtail millet proteins and causing losses of nutrients due to Maillard reaction. Superfine grinding can reduce the particle size of foxtail millet to obtain a better mouthfeel of foxtail millet products. The superfine foxtail millet flour has better solubility, higher freeze-thaw stability, and lower gelatinization temperature. Microbial fermentation contributes positively to reducing the molecular weight and retrogradation value of foxtail millet starch, degrading rapidly digested starch, and improving the digestibility of foxtail millet protein. This paper briefly introduced the effects of different processing methods on foxtail millet nutrients, aiming to provide references for increasing the variety and improving the quality of foxtail millet products.