The effect of pectinase and protease treatment on turbidity and on haze active molecules in pomegranate juice

• Pectin protein and phenol are involved in pomegranate juice turbidity development.
• A synergic clarifying effect of the pectinase and protease was demonstrated.
• Enzymatic treatments affect haze-forming activity of turbidity-causing molecules.
• Anthocyanin composition and juice color are not influenced by enzymatic treatments.

Juice clarification strategies have been developed in order to optimize the visual appearance of juice which strongly affects consumer behaviour. Clarity and color during post-bottling storage are important quality factors. This study examined the effects of pectinolytic and/or proteolytic clarification treatment on turbidity and on haze active molecules in pomegranate juice.A significant and synergic effect of the combined use of pectinase and protease enzymes was demonstrated and the best results in terms of turbidity levels of juice and potential haze formation were obtained. The data indicated that although pectinolytic and proteolytic treatments did not modify the total amount of pectins, proteins and phenols, they affected the haze forming activity of turbidity-causing molecules. It is important to note that enzymatic treatments of this kind did not modify anthocyanin composition and juice color. Therefore, this work contributes to improve the pomegranate juice processing in order to enhance quality attributes.