ABSTRACT
ABSTRACT: An efficient ultrasonic-assisted enzymatic extraction (UAEE) technique was developed for the extraction of phenolics from broccoli inflorescences, which is a rich source of phenolic compound, without organic solvents. The enzyme combination was optimized by orthogonal test: cellulase 7.5 mg/g FW (fresh weight), pectinase 10 mg/g FW and papain 1.0 mg/g FW. The operating parameters in UAEE were optimized with response surface methodology using Box-Behnken design. The optimal extraction conditions were as follows: ultrasonic power, 440 W; liquid to material ratio, 7.0:1 mL/g; pH value of 6.0 at 54.5◦C for 10 min. Under these conditions, the extraction yield of phenolics achieved 1.816 ± 0.0187 mg GAE/g FW. Compared with UAE and EAE, UAEE had expressed the better characteristic of the highest TPC value.
