Development of a low-temperature and high-performance green extraction process for the recovery of polyphenolic phytochemicals fromwaste potato peels using hydroxypropyl β-cyclodextrin

Potato peels, the humble scraps of the food industry, hide a treasure trove of antioxidants—and a new green method just unlocked them at room temperature, no harsh solvents needed.

Potato peels are a massive agri-food side-stream, but their potential as a source of antioxidant polyphenols has been largely locked behind water-ethanol solvents. Now, scientists have developed a simpler, greener key: hydroxypropyl β-cyclodextrin (HP-β-CD), a cyclodextrin derivative that acts like a molecular cage for polyphenols.

After fine-tuning the concentration, the team used response surface methodology to optimize the process. The result? A total polyphenol yield of 17.27 ± 0.93 mg chlorogenic acid equivalent per gram of dry mass—at just 30°C. Cranking up the heat to 80°C didn't help; near-ambient temperature was the sweet spot.

The HP-β-CD extracts were slightly richer in polyphenols than those from conventional solvents like aqueous ethanol or methanol, with similar antioxidant activity. The main players identified were neochlorogenic, chlorogenic, caffeic, and ferulic acids.

This isn't just a lab trick—it's a proof that waste can become a high-value bioresource with a simple, energy-saving, and eco-friendly process.

Key Points

• Green extraction using HP-β-CD yields 17.27 mg/g polyphenols at 30°C.
• Near-ambient temperature outperforms higher temperatures up to 80°C.
• Extracts richer than conventional solvents with similar antioxidant power.