The quality of cloudy apple juice seems to be better than the clarified juice due to the loss of
phenolic compounds during processing. Enzymatic browning and cloud stability are the main
problems in processing and storage of the juice. In this work, HPCD is proposed as an
alternative to the traditional heat treatments that can degrade the quality of the juice.
Polyphenol oxidase (PPO) and pectin methylesterase (PME) inactivation by HPCD were
determined for both enzymes. The effect of stirring speed on PPO inactivation was studied;
obtaining that at higher speed inactivation was also higher. Other quality parameters in the
juice were also determined after HPCD treatment, such as particle size distribution, colour,
turbidity and total phenolic compounds.
