Eugenol-loaded Pickering emulsions with antifungal activity for extending the postharvest shelf life of sweet cherries

Stable Pickering emulsions prepared by loading eugenol into chitosan-based particles • Strong antifungal activity exerted against Aspergillus niger and Penicillium citrinum • Quality deterioration of cherries delayed through Pickering emulsion coating Cherries, as non-climacteric fruits, are prone to browning, softening, and decay due to their thin skin and high respiration rate. Eugenol possesses broad-spectrum antimicrobial and antioxidant activities, but its application is limited by high volatility and poor water solubility. In this study, a chitosan-stabilized Pickering emulsion was developed to encapsulate eugenol and improve its stability and utilization. The antifungal activity of the emulsion against Aspergillus niger and Penicillium citrinum was evaluated, along with its effects on storage quality of fresh sweet cherries. The prepared emulsion exhibited an average particle size of 11.03 ± 0.67 μm and a zeta potential of 30.40 ± 0.56 mV, and remained stable under acidic conditions and below 60 °C. EUPE showed good antifungal activity against A. niger and P. citrinum , with inhibition zone diameters of 20.63 ± 0.06 mm and 20.12 ± 0.96 mm, respectively. When the EUPE concentration exceeded 8 mg/mL, the spore inhibition rates against both fungi were higher than 95%. The EUPE/CMC coating maintained better firmness and gloss, while showing lower total soluble solids and malondialdehyde contents during storage. The cherries maintained gloss and showed no mould growth. This work provides a promising strategy for natural postharvest preservation of cherries.