According to the method of Chen and Ono (2014), the distribution of the protein particle size was measured by laser light scattering using a series particle size analyzer (Beckman Coulter LS230) with a small volume module sample platform. The refractive index used for the dispersed phase was 1.570, and the correspondent to water was 1.333. Soymilk was diluted until the protein content was 0.1e0.3 mg/mL. Each sample was measured three times. The particle size distributionwas shown by the volume ratio of particles of different diameters.