Development and characterization of bioactive polymers for food packaging applications
- Autores: Alejandro Aragón Gutiérrez
- Directores de la Tesis: Rafael José Gavara Clemente (dir. tes.), Daniel Lopez Garcia (dir. tes.), Pilar Hernandez Muñoz (dir. tes.)
- Lectura: En la Universitat Politècnica de València ( España ) en 2025
- Idioma: inglés
- Tribunal Calificador de la Tesis: Juan López Martínez (presid.), Ana Beltrán Sanahuja (secret.), Luis Cabedo Mas (voc.)
- Programa de doctorado: Programa de Doctorado en Ingeniería y Producción Industrial por la Universitat Politècnica de València
- Materias:
- Enlaces
- Tesis en acceso abierto en: RiuNet
- Resumen
Antioxidant and antimicrobial packaging systems have emerged as an efficient technology to improve the stability and safety of food products. Thus, this doctoral thesis deals with the development and characterization of novel bioactive packaging materials using conventional melt-extrusion technologies. Two different polymer systems, i.e., an ethylene vinyl alcohol copolymer (EVOH) and a compostable blend comprising plasticized gliadins (TPG) and polycaprolactone (PCL), were used for the incorporation of different naturally occurring compounds, namely, ferulic acid (FA), cinnamaldehyde (CIN), methyl anthranilate (MA), and green tea extract (GTE). The antioxidant or antimicrobial activity of the selected compounds was firstly demonstrated, confirming their suitability for use as sustainable food preservatives.
Then, the influence of incorporating FA, CIN, and MA on the main physicochemical properties of the EVOH copolymer, as well as the effect of GTE on the PCL/TPG blend, was thoroughly studied. In addition, the active functional properties of the developed films, i.e., their antioxidant or antimicrobial activity, were determined based on the type of compound incorporated. Thus, EVOH-FA films exhibited potent antioxidant properties, and antibacterial activity in vitro against E. coli and S. aureus; EVOH-CIN films presented moderate antioxidant activity and a fungicidal effect against P. expansum. Furthermore, in EVOH-MA films, the antimicrobial activity of methyl anthranilate used in an active packaging system was demonstrated for the first time.
On the other hand, the addition of green tea extract, mainly consisting of catechins, to the blend comprising PCL and plasticized gliadins resulted in potent antioxidant activity and moderated antibacterial activity. The PCL/TPG-GTE film was used to conduct packaging tests on walnuts, demonstrating that the presence of GTE enhanced the stability of walnuts, resulting in decreased and delayed fat peroxidation.
