Abstract:Ultrasonic assisted enzymatic hydrolysis was used in peeling process to the yellow peaches (Jin tong 5). The optimum technological conditions were obtained by single-factor and response surface methodology. The quality of peeled yellow peach by ultrasonic assisted enzymolysis and non-assisted enzymolysis under the optimum conditions was compared. The results showed that the ultrasonic assisted optimum conditions were achieved as follows: ultrasonic power 450 W, temperature 45 ℃, time 30min, enzymes concentration 0.31 g/100 mL, pH 3.5, and liquid ratio W(yellow peach)V(enzyme solution) =13 (g/mL) with ultrasonic assisted method. And the results showed that the quality of peeled yellow peach was superior by ultrasonic assisted enzymolysis: rigidity was increased by 40% and chewing index was increased by 121%, the peeling efficiency was higher than non-assisted enzymolysis: enzyme concentration was reduced by 38% and enzymolysis time was reduced by 12%.