Effects of different salts on the gelation behaviour and mechanical properties of citric acid-induced tofu

To elucidate the effects of salts on the properties of citric acid-induced tofu gel, gelation was induced in the presence of KCl, CaCl2 or CaSO4, and gypsum tofu was used as a reference. The textural properties, water-holding capacity (WHC), rheological behaviour, aggregate size distribution and microstructure of the tofu were evaluated. The results indicated that the addition of 0.10 g/100 mL KCl,0.05 g/100 mL CaCl2 and 0.15 g/100 mL CaSO4 yields more elastic tofu with high water-holding capacity. The WHC of tofu induced in the presence of salts was similar to that of gypsum tofu, while the tofu was firmer and less elastic than gypsum tofu. The maximum elasticity of citric acid-induced tofu was obtained with addition of 0.15 g/100 mL CaSO4. These results are useful to understand the effects of different salts on soymilk gelation and provide a theoretical base for the quality improvement of citric acid-induced tofu.