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Before its use in food,
nanotechnology has been used in food packaging and food
contact materials to extend the shelf-life of packaged
foods.
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Nano coating on food
Apples in the US come
with a waxy coating to stop the fruit from losing
moisture and shriveling. Now nanotechnology provides
edible coatings as thin as 5nm for use in meats,
cheese, fruit and vegetables, as well as confectionery
and baked goods. These coatings provide a barrier to
moisture and gas exchange, and can deliver colours,
flavours, and antioxidants to preserve the appearance
of the products even after the packaging has been
opened. Edible antibacterial nano coatings have been
developed, which can be applied directly to bakery
goods to increase their shelf life.
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One of the earliest
commercial applications of nanotechnology in the food
sector is in packaging. It is estimated that between 400
and 500 nano packaging products are in commercial use now,
and the projection is that by 2020, nanotechnology will be
used in a quarter of all food packaging world wide.
The main purpose of nano
material in packaging is to increase the shelf life of
packed foods by reducing the rate of deterioration. This
is done by using packaging materials that will reduce gas
and moisture exchange with the atmosphere and minimize UV
light damage. For example, DuPont has produced a nano
titanium dioxide plastic additive which can reduce UV
damage in foods in transparent packaging. Nano packaging
can also be designed to release antimicrobials,
antioxidants, enzymes, flavours and nutraceuticals to keep
the packaged food tasting ‘fresh’ for a longer period.
Certain kinds of nano
packaging materials are made so as to interact with the
food to monitor its deterioration. Nano packaging using
carbon nanotubes is being developed with the ability to
‘pump’ out oxygen and carbon dioxide that would cause food
and beverages to deteriorate as well as undesirable odours
that make the food unappealing.
Nano-based
antimicrobial packaging
Food packaging and
containers are also made incorporating antimicrobial
nanomaterials, to prevent or slow down the decay of food
due to microbial action. These products commonly use
nanoparticles of silver but also nano zinc oxide and nano
chlorine dioxide. Packaging materials using magnesium
oxide, copper oxide and titanium dioxide in nano form as
well as carbon nanotubes are also being developed for use
in antimicrobial food packaging.
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Nanoscale
packaging and containers with antibacterial function |
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Company/ Institution
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Application |
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SongSing Nano
Technology Co., Ltd |
Cling wrap treated
with nano zinc oxide |
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Sharper Image |
Plastic storage bags
treated with nano silver |
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BlueMoonGoods, A-DO
Global, Quan Zhou Hu Zheng Nano Technology Co.,
Ltd and Sharper Image |
Storage containers
treated with nano silver |
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Daewoo, Samsung and
LG |
Refrigerators treated
with nano silver |
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Baby Dream® Co., Ltd |
Baby cup treated with
nano silver |
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A-DO Global |
Chopping board
treated with nano silver |
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SongSing Nano
Technology Co |
Tea pot treated with
nano silver |
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Nano Care Technology
Ltd |
Kitchenware treated
with nano silver |
Source: - Friends of
the Earth, 2008
Safety
Developing countries have
begun to use nanotechnology in the absence of health and
safety guidelines. India along with other Asian countries
like China, Sri Lanka, Thailand and Vietnam is moving
ahead to commercialise nanotechnology but there is as yet
no public debate on its impacts, nor a regulatory regime.
In India the government
is spending over US$6 million each year on nanotechnology
research but regulatory oversight remains weak. Firms are
getting ready to put out water filters using nanomaterials
for better absorption of contaminants but reportedly, the
companies have not performed any toxicology tests because
they are not required to do so.
There are outstanding
concerns about what happens to nanoparticles once they
are inside the body ; do they remain embedded or move
freely ? they are known to be highly interactive so what
are the immune or inflammatory responses they elicit ?
The behavior of a nanoparticle varies according to size,
shape, surface area and chemistry with the compounds it
interacts with. Exhaustive safety studies are needed
before nanotechnology is permitted to be used in the food
and beverage sector. |
