Antibacterial properties of nanofibers containing chrysanthemum essential oil and their application as beef packaging

This study was aimed to develop novel antibacterial packaging materials in order to reduce the microbial contamination of food surface. Chrysanthemum essential oil (CHEO) was successfully incorporated into chitosan nanofibers (CS/NF) through electrospinning which was demonstrated by SEM and AFM analysis. The antibacterial mechanism of CHEO against Listeria monocytogenes (L. monocytogenes) was explored as well. The cell membrane permeability of L. monocytogenes appeared to be increased by CHEO. In addition, respiratory metabolism of L. monocytogenes was inhibited by CHEO through the inhibition of the Embden-Meyerhof-Parnas (EMP) pathway. The presence of CHEO had a negative effect on the activity of hexokinase, phosphofructokinase and pyruvate kinase in L. monocytogenes cells. Release efficiency study indicated that the CHEO could be released slowly from CHEO/CS/NF to achieve long-lasting antibacterial effect. The antibacterial application of the CHEO nanofibers against L. monocytogenes was tested on beef, with an inhibition rate of 99.91%, 99.97%, and 99.95% at the temperature of 4 °C, 12 °C and 25 °C, respectively, after 7 days of storage. Beef parameters like thiobarbituric acid reactive substances (TBARS), pH values, and texture at different storage temperatures (4 °C, 12 °C and 25 °C) were evaluated as well. Due to the presence of antioxidant components in CHEO released from CHEO/CS/NF, the TBARS value in treated beef was 0.135 MDA/kg lower (P < 0.05) than the untreated sample at 4 °C after 12 days. PH value assay indicated that PH value of beef sample packed with CHEO/CS/NF (6.43) was lower than unpacked sample (7.05) at 4 °C after 10 days of storage. These obtained results all illustrated the fact that CHEO/CS/NF could prolong the shelf-life of beef, suggesting a potential application in food packaging.