The plant-based meat substitutes have been actively developed for the sustainable food production. In this study, we attempted to fabricate the soy protein-based fibers imitating the meat fiber texture by wet spinning technique. The precursor solution containing soy protein isolate and sodium alginate was continuously injected into a calcium chloride solution, resulting in the formation of fibers due to the gelation of alginate cross-linked by calcium ion. The fiber diameter was a few times larger than those of meat muscle fibers and controllable by the speed of rotating collector. The protein content of fiber was close to those of meats, and slightly increased by increasing the soy protein concentration of precursor solution. The mechanical strength of assembled fiber block was almost independent of the soy protein concentration, and was controllable by the sodium alginate concentration of precursor solution. The grilled fiber block had the mechanical strength between those of grilled pork and beef, demonstrating its potential applicability to the meat substitute with simulated nutrition and texture.

We focused on the cooperative behavior of disks falling in a particle bed, which five-disk shows upward and downward convex configurations repeatedly during the disk falling. We used DEM simulation to investigate the effects of the bed particle physical properties (density, diameter, and frictional coefficient) on the falling behavior. Here, we also used 10 different initial packing structures of the bed to investigate the effects of the packing structures on the falling behavior. As a result, when particle mass increased owing to changing density and diameter, the occurrence of the cooperative behavior depended on the packing structure. This leads to decreasing occurrence probability of the cooperative behavior. On the other hand, the occurrence probability is independent of particle frictional coefficient. This is because particle mass is a significant parameter, and the mass would affect contact force distributions of disks and the bed particle flow direction during the disks falling.

Non-spherical particle motion was analyzed and modeled by means of the direct numerical simulation of the six degrees of freedom motion with the Arbitrary Lagrangian-Eulerian method in which the effect of particle rotation and oscillation could be considered. In addition, the proposed motion model was implemented into the point-source based Eulerian-Lagrangian large-eddy simulation code and applied to the coaxial jet flow. Results showed that the behavior of the spherical and non-spherical particles’ dispersion observed in the experiments could be captured precisely by the computation. Moreover, the particle dispersion was discussed in detail with the dispersion width and the radial distribution function. It was suggested that the characteristics of the particle dispersion was characterized by the apparent Stokes number which the particle size distribution and the particle shape significantly affects.

Recently, utilization of biomass (i.e. domestic waste, excess sludge, food processing waste, etc.) is getting an attention as a promising way to realize economical low-carbon society goal. This paper provides a summary of current trends in biomass utilization regarding methane fermentation and sludge recycling technology. Methane fermentation is the process involved the conversion of organic waste to methane gas, which is being used for electricity generation and as fuel. As a plentiful of excess sludge is generated from sewage and night soil treatment plants daily, the recycle technology for biomass utilization is developed. For example; excess sludge and night soil are efficiently dewatered by shaft sliding screw press (to achieve 70% or lower moisture content) and utilized as a combustion improver. In addition, phosphorus in the thickening filtrate generated from the dewatering system is recovered through phosphorus recovery system and utilized as an agricultural fertilizer.