Abstract:

As a reducer, sdium sulfite can cleave the protein disulfide bonds and enhance the functional properties of protein. In the present study, rapeseed meal was hydrolyzed by Alcalase in the presence of sdium sulfite. The effects of sodium sulfite on the proteolysis rate and the functional properties of the hydrolysates were investigated. Results showed that the degree of hydrolysis (DH) at 120 min with the addition of sodium sulfite was 1.6 times of that in the absence of sodium sulfite. However, the emulsifying capacity, foaming capacity and foaming stability of the hydrolysates were decreased by the addition of sodium sulfite, which may be caused by the higher DH. On the other hand, the oil adsorption and foaming stability of the hydrolysates could be increased by ultrafiltration and diafiltration.

Key words: rapeseed, protease, sodium sulfite, degree of hydrolysis, functional properties