Food Marketing & Technology - India May 2019 | Page 40

Packaging
EDIBLE PACKAGING AND
MARKET OVERVIEW
and they may substitute synthetic
polymer films. Among other benefits
they can also be used to encapsulate
flavor/aroma
compounds,
antioxidants, antimicrobial agents, and
vitamins.
BY: DR P.A. RAAJESWARI** AND R. PRAGATHEESWARI*
S
ynthetic polymers developed
for innumerable purposes get
couched up and struck in the
ecosystem without getting degraded,
which also adds toxic chemicals to
the surroundings; invariably affecting
the entire lives of this era. Packaging
films being used in the food sector
contributes accountably higher for
this built up, which affects the food
chain and causes an imbalance in the
living system. The packaging alone is
responsible for approximately one-
third of the world’s garbage. This is
a big concern among the food and
packaging manufacturers and they
are continuously making efforts to
develop packages that can be recycled,
in order to reduce the amount of waste.
In this scenario, edible packaging plays
a very important role in minimising
packaging material wastage from a
sustainability perspective.
Nature: The Source of Inspiration
The concept of using an edible film
or coating to extend the shelf life of
fresh foods and protects them from
harmful environmental effects is not
a novel one. In fact, the idea derives
from the natural protective coating
such as the skin of some fruits and
vegetables. Covering foods with lipid
substances like waxes and fats to retard
desiccation is a very old practice. For
example, hot-melt paraffin waxes
became commercially available in the
1930s for coating citrus fruits to retard
moisture loss, and carnauba wax oil-
in-water emulsions were developed in
the early 1950s for coating fresh fruits
and vegetables.
films, sheets, coatings and pouches.
Edible films and edible sheets differ
from each other by their thickness,
e.g. edible films have thickness <254
μm and edible sheets have thickness
>254 μm. These are the stand-
alone structures that are preformed
individually from the food and then
placed on or between food parts or
sealed into edible pouches, whereas
edible coatings are skinny layers of
edible materials formed directly onto
the surface of the food.
Edible films and coatings have
similarities in their functions with
synthetic and inedible packaging films,
such as: barriers against water vapour,
gases and flavour compounds; and
protecting the food from mechanical
damage, physical, chemical and
microbiological activities.
Edible films and coatings have gained
considerable attention over the last
few years because of their advantages
over synthetic films. These films
could contribute to the reduction of
environmental pollution, improve the
recyclability of packaging materials,
Fundamentals of Edible
Packaging
Edible packaging comprises of edible
Food Marketing & Technology
40
May 2019
Components of Edible
Films and Coatings
A wide variety of polysaccharides,
lipids, proteins, etc. obtained from
protein and animal sources have
been used alone or in combination
to develop edible films, sheets and
coatings. They are described below:
Polysaccharides: Polysaccharide films
exhibit excellent oxygen, aroma, and
oil barrier properties and they provide
good strength and structural integrity.
However, they provide very little
resistance to water migration. The
excellent oxygen barrier properties
are because of their tightly packed,
ordered hydrogen-bonded network
structure and low solubility. The
coatings using polysaccharides may
retard ripening and help in increasing
the shelf life of coated produce. Some
of the polysaccharides that have been
used in edible packaging formulations
are: starch; cellulose; hemicelluloses;
chitosan; and gums.
Lipids: Lipid compounds have been
utilised as protective coatings for many
years but since they are not polymers,