Abstract: five functional and two nutritional properties of rice protein at various deamidation levels were assayed including solubility, emulsifying capacity and stability, foamability and foam stability, water bonding capacity, fat bonding capacity and the amino acids composites with in vitro digestion. The results showed that in the deamidation range of 0～63.5%, the solubility at pH7.0 of modified protein linearly increased to 99.4% but if the deamidation range, exceeded 63.5%, the solubility decrease a little. The modified proteins have had the optihum emulsifying capacity and stability within the 25.1%～33.4% deamidation levels, while in the 59.5% deamidation levels the foamability and foam stability were better. In addition, the water bonding capacity and fat bonding capacity of deamidational rice protein could respectively improve 1.55～1.78 times and 3.28～3.64 times. Deamidational modification was beneficial to the nutrition of rice protein for its amino acids content and digestion avelocity being improved.

Key words:  rice protein, acidic deamidation, functional property, nutritional property