Edible Film Preparation Using Chitosan/Gelatin/Phlorotannin-Embedded Limosilactobacillus fermentum FUA033 for Strawberry Preservation

In this study, we prepared edible films using chitosan/gelatin/phlorotannins (CGPs) embedded with probiotics and evaluated their preservation effects on strawberries. Edible films encapsulating <i>Limosilactobacillus fermentum</i> FUA033 (CGPFUA033) were prepared using the casting method. The intermolecular interactions, crystal structure, thermal stability, and morphology of the films, both prior to and following the incorporation of <i>L. fermentum</i> FUA033, were characterized using FT-IR, XRD, TG, and SEM analyses. The preservation efficacy of the edible films, with and without encapsulated <i>L. fermentum</i> FUA033, was assessed by monitoring the physical, chemical, and microbial properties, as well as the visual quality, of strawberries during a eight-day storage period. The results showed that encapsulation of <i>L. fermentum</i> FUA033 enhanced intermolecular interactions and thermal stability within the film matrix but did not significantly affect the crystalline structure of the edible film. At 0, 2, 4, 6, and 8 days, the CGPFUA033 treatment had preservation effects: the weight loss was 30.70 ± 1.53%, the total soluble solid content was 8.83 ± 0.28%, the decay index was 45.33 ± 1.53%, the malondialdehyde content was 7.44 ± 0.13 μmol/g, firmness was 21.49 ± 0.83 N, and the ascorbic acid content was 43.51 ± 0.79 mg/100 g. The shelf life of strawberries was extended by six days in the CGPFUA033 treatment group. Therefore, the chitosan/gelatin/phlorotannin edible film embedded with <i>L. fermentum</i> FUA033 has high preservation effects on strawberries, highlighting that <i>L. fermentum</i> FUA033 can be used as a probiotic for enhancing food preservation.