High‐pressure carbon dioxide and thermosonication technologies were applied to cloudy apple juice to determine their effect on polyphenol oxidase (PPO) and pectin methylesterase (PME) activity and other quality parameters right after the treatment and during storage at 4ºC for 28 days. Treatment conditions were 20 MPa, 45ºC, for 60 min and 20 kHz, 62ºC, 100% amplitude for 20 min, for pressurized CO₂ and thermosonication treatments, respectively. Both treatments showed a great impact on PPO activity and its residual activity steadily decreased during storage at 4ºC. In contrast, PME was found to be more resistant to the treatments. After both treatments, a homogenization effect was observed, which was also reflected in an increase in the cloud value of the juices after the treatments, kept during storage. Antioxidant capacity and total polyphenol content kept high levels during storage after both treatments.

中文翻译：

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高压二氧化碳和热超声处理后以及冷藏期间的酶失活和浑浊苹果汁的性质变化

处理后以及在4ºC下储存28天的过程中，将高压二氧化碳和热超声技术应用于混浊的苹果汁，以确定它们对多酚氧化酶（PPO）和果胶甲基酯酶（PME）活性及其他质量参数的影响。对于加压的CO ₂，处理条件为20 MPa，45ºC，持续60分钟； 20 kHz，62ºC，100％振幅，持续20分钟。和热超声处理分别。两种处理均显示出对PPO活性的巨大影响，并且其残余活性在4ºC储存期间稳定下降。相反，发现PME对治疗更抗。两种处理后均观察到均质化效果，这也反映为处理后果汁在储存期间保持的浊度增加。两种处理后的储存期间，抗氧化能力和总多酚含量均保持较高水平。