Sustainable Valorization of Avocado By-Products: Green Extraction of Phenolics with NaDES and Their Use in Fresh-Cut Fruit Preservation

What if the avocado peel you toss away could help keep your next avocado fresh? Scientists have found a green way to turn this by-product into a natural preservative.

The humble avocado peel, often discarded, is actually a treasure trove of phenolic compounds—natural antioxidants. But getting them out usually involves harsh chemicals. Enter NaDES, natural deep eutectic solvents, a new class of green solvents that are both effective and environmentally friendly.

In this study, researchers used ultrasound to shake phenolics loose from Hass avocado peels using several NaDES formulations. They tested lactic acid, glycerol, and citric acid as partners to choline chloride. The lactic acid-based NaDES won, pulling out the most phenolics and keeping them stable for eight weeks, even when exposed to light.

But the story doesn't end at extraction. The team applied this phenolic-rich extract to fresh-cut avocado slices. The result? A boost in phenolic content and better color stability over seven days of refrigerated storage, meaning less browning and a longer shelf life.

This circular approach—turning waste into a functional food additive—shows that sustainability and practicality can go hand in hand. The lactic acid NaDES emerges as a promising green solvent for both recovering valuable compounds and preserving fresh produce.

Key Points

• Lactic acid NaDES extracted most phenolics from avocado peel.
• Extract stayed stable for 8 weeks, even in light.
• Treatment boosted phenolics and reduced browning in fresh-cut avocado.