Abstract: A commercial soybean milk machine with laboratory modifications for adjustable heating power and rotation speed was used to investigate the effects of blender structure and its force on soybean milk quality. The results showed that larger angle of blender elevation α provided larger strike force and smaller tangential force, and smaller soybean residue rate and smaller granule size and harness of soybean residue were obtained, which could cause the transfer of more nutrients from soybean milk to residue, the reduction in the contents of protein, free amino acids, total sugars and fat, and the increase in viscosity. Larger axial force resulted in more homogenous stirring of materials and more even temperature distribution. Furthermore, cutter diameter showed a significant correlation with the hardness of soybean residue, and the axial angle of cutter tooth was also significantly correlated with solid content, viscosity, protein content and total sugar content.

Key words: soybean milk machine, soybean milk quality, blender structure, force effect