Foods (Feb 2024)

Active Low-Density Polyethylene-Based Films by Incorporating α-Tocopherol in the Free State and Loaded in PLA Nanoparticles: A Comparative Study

  • Ana G. Azevedo,
  • Carolina Barros,
  • Sónia Miranda,
  • Ana V. Machado,
  • Olga S. Carneiro,
  • Bruno Silva,
  • Mariana A. Andrade,
  • Fernanda Vilarinho,
  • Margarida Saraiva,
  • Ana Sanches Silva,
  • Lorenzo M. Pastrana,
  • Miguel A. Cerqueira

DOI
https://doi.org/10.3390/foods13030475
Journal volume & issue
Vol. 13, no. 3
p. 475

Abstract

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In this work, alpha-tocopherol (α-TOC) was encapsulated in poly(lactic acid) nanoparticles (PLA NPs) and added to low-density polyethylene (LDPE) films with the aim of producing an active film for food packaging applications. PLA NPs loaded with α-TOC were produced through nanoprecipitation and dried using two methods (freeze-dryer and oven). LDPE-based films with final polymeric matrix concentrations of 10 and 20 g/kg were then produced through blow extrusion. The results showed that LDPE-based films loaded with α-TOC can be produced using blow extrusion, and a good distribution of PLA NPs can be obtained within the LDPE matrix as observed using scanning electron microscopy (SEM). The mechanical properties were affected by the incorporation of α-TOC and PLA NPs loaded with α-TOC, with the observation of a decrease in tensile strength and Young’s Modulus values and an increase in elongation at break. Regarding water vapor permeability, the films showed a reduction in the values with the addition of α-TOC and PLA NPs loaded with α-TOC compared to the LDPE film (control). Films with α-TOC in the free state and loaded in PLA NPs showed antioxidant activity, but their behavior was affected by the encapsulation process.

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