Abstract:Using Vaccinium uliginosum fruit as raw material，V. uliginosum pectin （VUP） was extracted by ultrasonic-assisted enzyme method. The VUP extraction process was optimized through response surface analysis experiments. The de-esterification of VUP was realized by enzymatic modification to obtain modified V.uliginosum pectin （MVUP）. The results indicated that the optimal extraction process was a solid-to-liquid ratio of 1∶40（g/mL），a methyl esterase dosage of 0.07 g，an ultrasonic time of 55 min，an ultrasonic temperature of 45 ℃，and a pH value of 3.5. Under these conditions，the VUP yield was 9.82%. The physicochemical property results demonstrated that compared with VUP，MVUP exhibited a higher water-holding capacity and galacturonic acid content，both in line with relevant national standards for pectin. The antioxidant results revealed that both MVUP and VUP exhibited potent ABTS+，DPPH·，and ·OH free radical scavenging effects.