Quince seed mucilage films incorporated with oregano essential oil: Physical, thermal, barrier, antioxidant and antibacterial properties

Abstract

Quince seed mucilage (QSM) films containing oregano essential oil at 1, 1.5 and 2% v/v were prepared to examine their antibacterial, antioxidant, physical, thermal, microstructural and mechanical properties. Addition of 1% oregano essential oil did not affect the oxygen and water vapor permeability of the films. Incorporating OEO, increased total color differences (ΔE) and decreased whiteness index (WI). A decrease of elastic modulus (EM) and tensile strength (TS) accompanied with an increase in elongation at break (%EB) was observed with increasing oil concentration up to a level of 2.0% (w/w). Antimicrobial and antioxidant properties significantly increased with the incorporation of EO (p < 0.05). The antimicrobial activity of the QSM films incorporated with oregano essential oil was screened against 11 important food-related bacterial strains by agar disc-diffusion assay. Films containing 1% of OEO were not effective against Salmonella typhimurium and Pseudomonas aeruginosa but exhibited a strong inhibitory effect on the growth of Staphylococcus aureus, Escherichia coli, Shewanella putrefaciens and Yersinia enterocolitica as evidenced by minimal growth around the film cuts. Our results pointed out that the incorporation of oregano essential oil as a natural antibacterial agent has potential for using the developed film as an active packaging.