This study aimed to develop bioactive nanoemulsion (NE)-impregnated polysaccharide films to extend the shelf life of mushrooms. A stable and well-dispersed NE was prepared using 5 wt% soy protein (SP) and 10 % (v/v) lavender essential oil (LEO) through 10 min of ultrasound treatment, resulting in a droplet size of 152.3 nm, a polydispersity index (PDI) of 0.17, and a ζ-potential of −43.4 mV. Two types of films were prepared by incorporating 5 % and 10 % (v/v) SP/LEO NE into a curdlan (CD) and chitosan (CS) composite matrix, forming CD-CS-NE1 and CD-CS-NE2 films, respectively. The CD-CS-NE2 films possessed the highest tensile strength (14.5 MPa) and elongation at break (140 %). FTIR and molecular docking studies confirmed strong intermolecular interactions between the CD, CS, and NE components. The antibacterial activity of the NE-impregnated CD-CS films was significantly enhanced, with inhibition zones of 22 mm and 26 mm for Escherichia coli and Staphylococcus aureus, respectively, in the CD-CS-NE2 film. Growth curve and colony-forming unit (CFU) analyses further supported the superior antibacterial performance of the CD-CS-NE2 film. In mushroom storage tests, the CD-CS-NE2 film extended the shelf life of button mushrooms to 12 days and straw mushrooms to 4 days. Additionally, it reduced weight loss to 3 % and 4 % in button and straw mushrooms after 12 and 4 days, respectively. Mushrooms treated with CD-CS-NE2 film maintained higher firmness, with values of 18 N for button mushrooms and 6 N for straw mushrooms. The films effectively suppressed polyphenol oxidase (PPO) activity and browning. Overall, these findings suggest that SP/LEO NE-impregnated CD-CS films have strong potential for improving food preservation and reducing spoilage, particularly in fresh produce like mushrooms.
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