Fabrication and characterization of LDPE/silver-copper/titanium dioxide nanocomposite films for application in Nile Tilapia (Oreochromis niloticus) packaging
Abstract:
Proper packaging is an essential issue in seafood safety leads to the
preservation of food quality and extending the shelf life.
In this study, fabrication and characterization of LDPE/Ag/TiO2 and
LDPE/Ag+Cu/TiO2 nanocomposite flms for application in Nile Tilapia
packaging were evaluated. After investigation of scanning electron
microscopy (SEM), energy-dispersive
X-ray spectroscopy (EDS), disk difusion test, minimum inhibitory
concentration, and minimum bactericidal concentration,
the antimicrobial efect of produced nanocomposite flms was evaluated on
the Tilapia fsh samples stored at 4 °C and −20 °C
for 5 and 10 days. Chemical features (pH, protein and fat
concentrations, and free fatty acid profle) of the Tilapia fsh covered
with the produced nanocomposites and nanoparticle migration were also
assessed. EDS and SEM techniques confrmed the
presence of nanoparticles on the polymer surface and their relative
homogeneity. The antibacterial tests of LDPE/Ag+Cu/
TiO2 nanocomposite flm exhibited strong antibacterial activities against
Escherichia coli and Listeria monocytogenes
bacteria (P=0.000). The microbiological tests revealed that
Ag+Cu-contained flm had signifcantly higher antimicrobial
efcacy on the Nile Tilapia samples (P<0.05). The overall result of
the series of chemical experiments showed that Tilapia
samples packed in Ag+Cu flm had the least changes in chemical properties
compared to fresh samples (P<0.05 for pH,
fat concentration, and free fatty acid profle). Besides, the migration
of Ag and Cu nanoparticles from the flm to Tilapia
samples was slightly (the amount of Ag and Cu release was <2.0 µg/Kg
and <10 µg/Kg, respectively). From the obtained
results, it could be concluded that a flm containing 2.5% silver, 2.5%
copper, and 5% titanium dioxide nanoparticles had
the most signifcant antimicrobial efect on the Nile Tilapia fsh.
Therefore, using LDPE/Ag+Cu/TiO2 nanocomposite flm
can be a promising approach to create active packaging in the seafood
industry.