Nanotechnology in Food & Agriculture - denix

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ingredients delivers greater bioavailability,
improved solubility and increased
potency compared to these substances
in larger or micro-encapsulated form
(Mozafari et al. 2006). This is touted as
delivering consumer benefits. The greater
potency of nanoparticle additives may
well reduce the quantities of additives
required, and so benefit food processors.
However the greater potential for cellular
uptake of nanomaterials, coupled with
their greater chemical reactivity, could
also introduce new health risks.
Modern food processing methods
produce nanoparticles
The emerging discussion of potential
health risks associated with nanomaterials
in foods has largely focused on
manufactured nanomaterial food or food
packaging additives and has ignored
nanoparticles created during processing.
However nanoparticles are also present in
many foods because of the technology
used to process the foods, rather than
because they are food additives or
ingredients. Although food processing
technologies that produce nanoparticles
are not new, the rapidly expanding
consumption of highly processed foods is
most certainly increasing our exposure to
nanoparticles in foods.
Processing techniques which produce
nanoparticles, particles up to a few
hundred nanometres in size, and
nano-scale emulsions are used in
the manufacture of salad dressings,
chocolate syrups, sweeteners, flavoured
oils, and many other processed foods
(Sanguansri and Augustin 2006). The
| NANOTECHNOLOGY IN FOOD & AGRICULTURE
formation of nanoparticles and nanoscale
emulsions can result from food processing
techniques such as high pressure valve
homogenisation, dry ball milling, dry jet
milling and ultrasound emulsification.
Although many food manufacturers may
remain entirely unaware that their foods
contain nanoparticles, it is likely that these
processing techniques are used precisely
because the textural changes and flow
properties they produce are attractive to
manufacturers.
Recent research has also found
in food nanoparticles which can
best be described as contaminants.
Nanopathology researcher Dr Antonietta
Gatti has found that many food
products contain insoluble, inorganic
nanoparticles and microparticles that
have no nutritional value, and which
appear to have contaminated foods
unintentionally, for example as a result of
the wear of food processing machines
or through environmental pollution (Gatti
undated; Personal communication with
Dr A.Gatti 19 September 2007). Gatti and
colleagues tested breads and biscuits
and found that about 40% contained
inorganic nanoparticle and microparticle
contamination (Gatti et al. submitted for
publication).
While this report focuses on the issues
associated with the intentional addition of
nanomaterials to foods, food packaging
and agricultural products, we recognise
that the health implications of food
processing techniques that produce
nanoparticles and nanoscale emulsions
also warrant the attention of food
regulators. The potential for such foods to
pose new health risks must be investigated
in order to determine whether or not
related new food safety standards are
required. Just as a better understanding of
the health risks of incidental nanoparticles
in air pollution have resulted in efforts
to reduce air pollution, improved
understanding of the health risks
associated with incidental nanoparticle
contaminants in foods may also warrant
efforts to reduce incidental nanoparticles’
contamination of processed foods.