antimicrobials with the cheaper ones would still account to higher antimicrobial
activity (Chana-Thaworn et al. 2011).
Presently, the production and marketing of eco-friendly cum biodegradable
packaging materials have higher scopes in developing countries. However, in
many cases the petroleum-derived polymers such as polystyrene and polyethylene
still rule the packaging industry, posing severe threats to global concerns (Bitencourt
et al. 2014). This leads to problems concerned with performance, processing, and
costing, all of which are still big questions for these non-renewable materials. In this
context, various types of materials used for packaging of food products have been
reviewed earlier based on the biopolymer that includes both coatings, edible films
along with packaging materials (Aloui et al. 2014). Tables 15.1 and 15.2 summarize
reported examples of different types of biodegradable matrices with additives.
Rationally, the use of either biodegradable and renewable materials composed of
polysaccharides, proteins, lipids, polyesters or even a combination of all can turn out
to be an effective solution to these problems.
In addition to that, some useful additives such as antioxidants, colorants, and
antimicrobial agents can provide some functional properties to the packaging
materials in order to inhibit or delay microbial or chemical spoilage of packaged
food items.
15.2.1 Moisture Absorbers
Food products are required to control free water in order to enhance their shelf life.
The presence of seeping liquids such as blood or other fluids in fish and meat
products lessens the quality of the food items. An excess amount of water inside
the packaged foods favors the growth of microbes, causing softening of food
products like cookies and biscuit as well as hardening freeze-dried coffee and milk
powder. On the other hand, excessive water loss may also promote the oxidation of
fat. Thus, organic acids have been incorporated into the absorbent pads to inhibit the
growth of microorganisms in these nutrient-rich foods. The entire mechanism is
based upon the absorption process, which tends to either remove excess water or
control the relative humidity in the headspace depending on the requirement. This
demands the use of highly hygroscopic and dehydrating agents such as polypropylene glycol, cellulose fibers, carbohydrates, minerals, polyacrylate salts, molecular
sieves, silica gel, and calcium oxide, etc. The size and weight of food, as well as the
initial water activity of the absorber, absolutely determine the type of moisture
absorber to be selected. Moreover, factors like humidity and temperature of the
storage foods, the transmission of water vapor from the packaged foods, and
sensitivity of food towards the moisture play essential roles (Liz et al. 2013).
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B. Mishra et al.
activity (Chana-Thaworn et al. 2011).
Presently, the production and marketing of eco-friendly cum biodegradable
packaging materials have higher scopes in developing countries. However, in
many cases the petroleum-derived polymers such as polystyrene and polyethylene
still rule the packaging industry, posing severe threats to global concerns (Bitencourt
et al. 2014). This leads to problems concerned with performance, processing, and
costing, all of which are still big questions for these non-renewable materials. In this
context, various types of materials used for packaging of food products have been
reviewed earlier based on the biopolymer that includes both coatings, edible films
along with packaging materials (Aloui et al. 2014). Tables 15.1 and 15.2 summarize
reported examples of different types of biodegradable matrices with additives.
Rationally, the use of either biodegradable and renewable materials composed of
polysaccharides, proteins, lipids, polyesters or even a combination of all can turn out
to be an effective solution to these problems.
In addition to that, some useful additives such as antioxidants, colorants, and
antimicrobial agents can provide some functional properties to the packaging
materials in order to inhibit or delay microbial or chemical spoilage of packaged
food items.
15.2.1 Moisture Absorbers
Food products are required to control free water in order to enhance their shelf life.
The presence of seeping liquids such as blood or other fluids in fish and meat
products lessens the quality of the food items. An excess amount of water inside
the packaged foods favors the growth of microbes, causing softening of food
products like cookies and biscuit as well as hardening freeze-dried coffee and milk
powder. On the other hand, excessive water loss may also promote the oxidation of
fat. Thus, organic acids have been incorporated into the absorbent pads to inhibit the
growth of microorganisms in these nutrient-rich foods. The entire mechanism is
based upon the absorption process, which tends to either remove excess water or
control the relative humidity in the headspace depending on the requirement. This
demands the use of highly hygroscopic and dehydrating agents such as polypropylene glycol, cellulose fibers, carbohydrates, minerals, polyacrylate salts, molecular
sieves, silica gel, and calcium oxide, etc. The size and weight of food, as well as the
initial water activity of the absorber, absolutely determine the type of moisture
absorber to be selected. Moreover, factors like humidity and temperature of the
storage foods, the transmission of water vapor from the packaged foods, and
sensitivity of food towards the moisture play essential roles (Liz et al. 2013).
312
B. Mishra et al.