摘要
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。高于600MPa的压力,失活PPO的效果开始显著。VC在500MPa以下对果汁中PPO有激活作用,在600MPa以上或热处理结合高压时有钝化PPO的作用。随着保压时间的延长和温度的升高,桃汁中多酚氧化酶相对活性逐渐降低。500MPa60℃或750MPa50℃以上的处理强度可使鲜榨桃汁中的PPO失去61%以上的活力。
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. The effect of pressure on the inactivation of PPO became remarkable when it was above 600 MPa. Adding VC activated PPO in the juice when the pressure was below 500 MPa but inactivated it when the pressure was above 600 MPa or combined with heating. The activity of PPO in the juice decreased gradually with the rise of heating temperature and the extension of pressure holding time. The treatment above 500 MPa and 60℃ or 750 MPa and 50℃ could inactivate the activity of PPO by 61%. PPO in the peach juice was hardly inactivated by high pressure.
出处
《饮料工业》
2007年第3期24-27,共4页
Beverage Industry
关键词
鲜榨桃汁
多酚氧化酶
超高压
酶促褐变
颜色
fresh peach juice
PPO
ultra high pressure
enzymatic browning
colour
