Abstract:In order to increase the extraction rate of pumpkin seed oil by enzyme-assisted aqueous extraction, using method of enzymatic combined chemical demulsification process by adding Bacillus licheniformis protease (pH 9~12) during emulsion from enzyme-assisted aqueous extraction of pumpkin seed oil. According to single factor experiment and response surface methodology, the best processes for enzymatic demulsification were: volume ratio of water to emulsion 0.9∶1 (mL/g), dosage of enzyme 3 078 U/g, hydrolysis temperature 51 ℃, hydrolysis time 2.5 h, and the demulsification rate of the verification experiment was 88.39%. The effect of adjusting the pH on emulsion stability and demulsification rate after enzymatic demulsification was analyzed. It was found that the demulsification rate increased to 95.47% when adjusted pH to 4.5 after enzymatic demulsification.