As the pressure increased,the activity of PPO in the juice reduced slowly in the pressure range of 200~500MPa,and 400 MPa could activate PPO in the juice.

• 桃汁中的PPO是耐高压的酶,200-500MPa的压力处理使果汁中PPO活力逐渐降低,但降低幅度不大,400MPa的压力对PPO有激活作用。