Cloud stabilization of citrus fruit juices treated with purified pectin methylesterase inhibitor from lemon (Citrus limon L.).

Abstract

Cloud destabilization is a significant quality defect of cloudy fruit juices. A proteinaceous inhibitor (PMEI) of pectin methylesterase (PME), identified in lemon, with a fold purity of 89.13, was used to stabilize the cloud of freshly prepared sweet lime, orange, and lemon juice. Lemon PMEI was able to inhibit the PME activity of all three fruit juices. In this study addition of calculated amounts of lemon PMEI to the three juice systems was based on the total PME units present in each juice. Relative turbidity, viscosity, pH, and ζ -potential of the PMEI-treated juices were stable, resulting in uniform distribution of cloud particles throughout the juice system. The sedimentation rate in PMEI treated juices was very low, with cloud particles having smaller particle size diameter. This work demonstrates an alternative option that might create new potential to control the quality deterioration in cloudy fruit juices. © 2022 Society of Chemical Industry.