Abstract: An immobilized enzyme roller was developed by immobilizing cellulase and neutral protease?onto polypropylene microporous membrane modified by?cellulose acetate,?respectively. Soybean flakes were rolled sequentially with the cellulose roller followed by the neutral protease roller and then used for the production of cold-pressed oil. Hydrolysis conditions were optimized by one-factor-at-a-time method and response surface methodology. An air relative humidity of 86.0%, an operating temperature of 55.0 ℃ and a rolling time of 91.0 min were found to be the optimal conditions to obtain a higher oil yield of 73.8% and a lower degree of protein denaturation. After seventh repeated use, both immobilized enzyme rollers retained more than 80% of their initial activities.

Key words: immobilized enzyme roller, sequential enzymatic hydrolysis, cold pressing method, oil yield, nitrogen solubility index (NSI)