Tofu Structure Is Regulated by Soymilk Protein Composition and Coagulant Concentration

摘要

Tofu is made from soymilk which is a turbid colloidal liquid. Tofu structure is related to soymilk components, particularly colloidal components such as protein particles and oil globules. Protein particle content increased with the increase of 11S/7S globulin ratio in soybeans. Tofu was made from the soybean mixtures having different 11S/7S ratio by adding coagulants of various concentrations. The tofu having high 11S/7S ratio showed a hard texture at low coagulant concentration, and the tofu having low 11S/7S ratio needed more coagulant for the maximum hardness. Before the tofu reached maximum hardness, the tofu structure had a large cell and thin wall of network, and after it reached the maximum hardness, its network structure showed a large cell with many holes and no flat wall. However, the tofu structure near maximum hardness had fine and even cells with the coagulant concentration of a changing point from increase of hardness to constant. Therefore, tofu from soybeans having larger 11S/7S ratios could have a fine structure with lower coagulant concentration.