Development of biobased multifunctional films incorporated with essential oils@polydopamine nanocapsules for food preservation applications

A novel multifunctional soy protein isolate-carboxymethyl cellulose (SPI-CMC) based nanocomposite film was successfully prepared by introducing the polydopamine encapsulated essential oils (EOs@PDA) nanocapsules for food packaging. The EOs@PDA nanocapsules possessed smooth spherical morphology with good dispersion, and the particle size was about 283 nm. The influence of EOs@PDA nanocapsules on the physical, chemical and biological properties of EOs@PDA/SPI-CMC nanocomposite film was investigated. The EOs@PDA nanocapsules were crosslinked with SPI-CMC matrix and distributed uniformly in the matrix. The nanocomposite film with 1 wt% nanocapsules (EP/S-C) also showed excellent antioxidant activity (66.6 ± 0.3 % on DPPH and 98.6 ± 0.1 % on ABTS), superior UV-blocking properties (100 %), advanced antibacterial ability against E. coli and S. aureus, favorable biodegradability (>90 %) and relatively low In vitro cytotoxicity. Also, the EP/S-C nanocomposite film displayed potential to extend the shelf life of fresh cut apple slices (>24 h), perishable cherry tomatoes and blueberries (>6 days). The results suggested that the EOs@PDA/SPI-CMC nanocomposite film had a great possibility in the field of biodegradable and antimicrobial materials for food packaging.