Abstract
Mechanical properties of tofu were investigated in order to control tofu processing. Several kinds of the elastic parameters were determined from the stress-strain curve of tofu, and the effect of lipid concentration on the elastic parameters in the small and large deformation conditions was analyzed from the viewpoint of emulsion gel. The tofu sample in which lipid or protein concentration was different was prepared from the same breed of soybean for the purpose of discussing the influence of lipid and protein significantly. The initial elastic modulus of high MgCl2 concentration tofu increased with increasing MgCl2 concentration, while its rupture stress decreased with increasing MgCl2 concentration. Therefore, the contribution of continuous phase would be large in initial elastic modulus, and disperse phase would be dominant in rupture stress. The rupture stress of tofu was shown to tend to harden in low lipid concentration when lipid concentration increased. On the other hand, when the lipid concentration condition was high, rupture stress of tofu decreased with increasing lipid concentration. Furthermore, we examined the applicability of the numerical model for the rupture stress of tofu. The model could be described the behavior of rupture stress depending on lipid and protein concentrations.
