Pectinase-assisted extraction of red dragon fruit (Hylocereus polyrhizus) juice: Process optimization and quality assessment

Red dragon fruit is a nutritional powerhouse, but its sticky, mucilage-rich flesh fights back against juice extraction—until pectinase steps in to break the barriers.

Red dragon fruit (Hylocereus polyrhizus) is packed with nutrients, yet its high mucilage and pectin content make extracting clear, high-yield juice a sticky challenge. Without processing, the fruit's natural polymers trap the juice. Enter pectinase, a green enzyme that breaks down pectin, improving both yield and clarity. But its use for red dragon fruit juice (RDFJ) had not been finely tuned—until now.

Researchers applied a Box-Behnken design to optimize three key parameters: enzyme concentration (0.1–0.5%), incubation temperature (35–55°C), and time (100–140 minutes). They tracked juice yield, total soluble solids (TSS), and viscosity. The winning formula: 0.3% enzyme at 45°C for 120 minutes, yielding 72.25% juice, 11.01°Brix TSS, and a low viscosity of 4.33 cP.

The optimized juice was then compared with a control (no enzyme). Pectinase treatment dramatically boosted quality: total phenolic content reached 192.72 mg GAE/100 mL, antioxidant activity hit 73.87% DPPH inhibition, and betacyanin—the pigment behind the red color—was 62.31 mg/100 mL. Reducing sugar and total sugar also rose, while vitamin C levels were lower.

This study shows that pectinase-assisted extraction is a powerful, green strategy to unlock the full potential of red dragon fruit, delivering more juice, more nutrients, and clearer liquid—without harsh chemicals.

Key Points

• Optimized pectinase extraction: 0.3% enzyme, 45°C, 120 min.
• Yield hit 72.25%, TSS 11.01°Brix, viscosity low.
• Boosted phenolics, antioxidants, betacyanin, and sugars.