Abstract:

In the present study, alkaline protease hydrolysis was used for the preparation of functional polypeptides from peanut protein. In order to optimize the enzymatic hydrolysis of peanut protein, the effects of temperature, pH, substrate concentration, enzyme amount on degree of hydrolysis (DH) and trichloroacetic acid nitrogen solubility index (TCA-NSI) were explored using response surface methodology. The optimal conditions for achieving both high DH and TCA-NSI were found to be hydrolysis temperature of 55 ℃, pH 8.4, substrate concentration of 4.31%, protease amount of 3.39% and hydrolysis time of 4 h. Under these optimal conditions, a DH of 23.40 and a TCA-NSI of 74.88% were obtained. The experimental values were consistent with the predicted ones with a relative error within 0.5%, indicating that these optimized hydrolysis conditions are reliable.

Key words: peanut protein, functional polypeptide, enzymatic hydrolysis, response surface methodology