Membrane separation process for flavor removal in concentrated coconut water

Overview

This research proposes a sequence of membrane separation processes to remove undesirable components from frozen concentrated coconut water (FC CCW). The primary targets are high molecular weight compounds responsible for spoilage and off-flavors, particularly enzymes such as polyphenol oxidase (PPO) and peroxidase (POD). The technology aims to deliver an economically viable route for producing high-quality concentrated coconut water by leveraging hollow fiber membrane modules and carefully controlled operating conditions to minimize fouling.

Technical specifications

Process sequence:

• Microfiltration pre-treatment to remove particulates
• Ultrafiltration with membranes of varying molecular weight cut-offs (100, 50, and 30 kDa) to remove macromolecules and enzymes
• Optional polishing steps using nanofiltration or pervaporation for further quality enhancement

Key technical considerations:

• Hollow fiber membrane modules preferred over flat configurations for industrial scalability
• Operating parameters including transmembrane pressure and Reynolds number will be optimized
• Fouling mechanism studies to develop mitigation strategies
• Flux decline monitoring and permeate characterization for performance validation
• Product acceptability evaluation to confirm sensory quality

The approach builds on prior work demonstrating successful enzyme removal from fruit juices, including bromelain separation from pineapple extract using appropriately selected molecular weight cut-off membranes.

Technology readiness level

The research is at an early-to-mid stage of development. Prior studies have validated ultrafiltration for coconut water sterilization using hollow fiber membranes, and dead-end filtration tests with 30 and 100 kDa membranes have shown substantial decreases in PPO and POD activity. The research group has additional experience with nanofiltration for enzyme removal and fouling characterization across multiple systems. Future work will focus on chemical composition analysis, systematic ultrafiltration testing across different membrane cut-offs and operating conditions, fouling mechanism elucidation, and product acceptability evaluation to advance toward commercial viability.