Several concerns must be addressed prior to commercial
use of biobased primary packaging materials. These
concerns include degradation rates under various conditions,
changes in mechanical properties during storage,
potential for microbial growth, and release of harmful compounds
into packaged food products. In reality, relatively
poor mechanical and high hydrophilic properties with poor
processibility of those biopolymer-based packaging materials
are causing a major limitation for their industrial use
. Protein and carbohydrate packaging films are generally
good barriers against oxygen at low to intermediate
relative humidity and have good mechanical properties;
however, their barrier against water vapor is poor due
to their hydrophilic nature. Though many research efforts
focused on improving the film properties of biopolymerbased
packaging films indicated a significant improvement
in film properties, their physical, thermal, and mechanical
properties are still not satisfactory and find difficulties in
industrial applications.
Recently, a new class of materials represented by
bio-nanocomposites with enhanced barrier, mechanical
and thermal properties has been considered as
a promising option in improving the properties ofthese biopolymer-based packaging materials.
Bio-nanocomposites consist of a biopolymer matrix reinforced
with particles (nanoparticles) having at least one
dimension in the nanometer range (1–100 nm). Bionanocomposites
are a new class of materials exhibiting
much improved properties as compared to the base
biopolymers due to the high aspect ratio and high surface
area of nanoparticles. Therefore, efforts have been devoted
to develop bio-nanocomposites for food packaging films
with improved mechanical, barrier, rheological, and thermal
properties