Abstract:

The hydrolysis of extruded full-fat soybean flakes by alkaline protease provides a promising method to extract
soybean oil, protein and polypeptide simultaneously. In order to control the enzyme-assisted aqueous extraction of oil from
full-fat soybean flakes, it is necessary to model the kinetics of the protein hydrolysis of extruded full-fat soybean flakes
and establish the relevant kinetic parameters. In this research, we developed a kinetic mathematical model for the alcalase
hydrolysis of full-fat soybean flakes as follows: R =（18.294 0E0 + 0.273 4ρ0) exp(-0.256 2DH), where E0 is the initial
concentration of alcalase, ρ0 is initial substrate concentration, and DH is degree of hydrolysis. The kinetic constant (K) of the
inactivation of alcalase during the hydrolysis process was determined to be 4.920 4 min-1. Our experimental data were well
fitted to the proposed kinetic model, proving that the mode has a high practical value.

Key words: soybean, enzyme-assisted aqueous extraction of soybean oil, protein hydrolysis, enzymatic hydrolysis kinetics