Abstract
The effects of the concentration and composition of salts on tofu gel hardness were studied. The effect of divalent cations such as magnesium and calcium on tofu gel hardness was remarkable. When the concentration of a salt that has a divalent cation was increased, tofu gel hardness generally increased. However, tofu gel hardness decreased when the magnesium chloride concentration was increased to more than 0.05 mol/l, compared with that in the case of calcium chloride. The effect of monovalent cations on tofu gel hardness was small. Even when the concentration of a salt that has a monovalent cation such as sodium chloride was increased, tofu gel hardness showed almost a constant value. For magnesium chloride-sodium chloride solution, it is suggested that sodium chloride does not significantly affect tofu gel hardness but contributes to the water retention of tofu.
