The effect of homogenization and addition of sodium sulphite, sucrose and lecithin was studied on the protein solubility of water soluble soybean extracts (WSSE). The heat treatment of the water soluble soybean liquid extracts at 90 ± 2°C for 15 minutes and drying had a large effect on the protein solubility, decreasing the nitrogen solubility index (NSI) from 90.57% in the dehulled soybean to 25.31% in WSSE used as control. However, the NSI values of the WSSE containing sucrose, sodium sulphite and lecithin as well as that one homogenized were significantly higher than the NSI of the WSSE (control) which recieved heat treatment only.
dried soybean milk; protein solubility; homogenization; disulfite bond-spliting reagent; heat treatment
