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| Caramels contain carbon nanoparticles. |
BRISBANE: Researchers have found carbon nanoparticles in foods, including bread, corn flakes, biscuits and caramels.
The presence of carbon nanoparticles in food caramels shows that it could be safe to eat them, according to research published in the journalScientific Reports.
“It is known that nanomaterials were used in dyeing hair, providing colorful glasses and in weapons. Now, our discovery of the presence of carbon nanoparticles in food caramels adds to the repertoire of traditional use of nanomaterials,” said one of the authors of the paper Arun Chattopadhyay from the Indian Institute of Technology in Assam, India.
Carbon nanoparticles
Nanoparticles are between 1 and 100 nanometres - 10,000 times smaller than the width of a human hair. Nanoparticle research holds potential in areas such as diagnostics, cancer detection, and targeted drug delivery.
But their safety has been questioned, particularly through the discovery of toxic nanoparticles in sunscreens. The reactiveness of nano-sized particles is difficult to assess, so properties are still relatively unknown.
Nanoparticles have also been known to pass through cell membranes and cause possible harm to otherwise healthy cells.
Many researchers have engineered nanoparticles for the use in biomedical applications but few biodegradable nanoparticles have entered clinical trials and the market place.
Nanoparticles in food
The researchers tested for the presence of carbon nanoparticles in different carbohydrate based food caramels, where food preparation involves heating in absence of water.
They found spherical carbon nanoparticles ranging from 4 to 30 nm in size in samples of bread, sugar-derived jaggery(extensively used in India), sugar caramel, corn flakes and biscuits. The nanoparticles also had similar properties to synthetic ones.
“If we and our ancestors have been eating these nanoparticles for centuries (if not for millennia) and if these particles can offer some benefits of nanomaterials – then why not use them?” Chattopadhyay said.
The nanoparticles had little or no toxicity
The carbon nanoparticles were extracted from the food sources surrounded by polymerized sugar. The researchers then tested for the toxicity of these extracted nanoparticles on animal cells and found that even at high concentrations, the nanoparticles had little or no toxicity.
“Imagine that if you could tweak the optical and other biochemical properties a bit then these particles could be used in food flavours and other applications without unnecessarily sacrificing the safety aspect,” said Chattopadhyay.
Being derived from readily available food sources, these carbon nanoparticles could be of competition to the current expensive synthetics as they would not need to go through as many extensive studies for safety concerns.
“They have the potential to improve public perception on the safety of nanoparticles. This does not still mean that all nanoparticles are safe. Some are and some are not,” said Chattopadhyay.
“This could demonstrate to people that we have been eating nanoparticles for many years,” said material scientist Marc in het Panhuis from the University of Wollongong, in Australia.
He finds the study very interesting but cautions that the relative safety of nanoparticles highly depends on the application they are used for. “It all depends on what they add to the nanoparticles [once they are extracted from the food], any addition can change the properties of the material and in turn the safety of it,” he said.
Fonte: Cosmos
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Vejam:
a) Food-based natural nanoparticle discovery opens debate on safety
