Nanotechnology for Food Packaging

‘Nano’ or small-scale technologies are an exciting area of science involving work at the nano scale; far smaller than micro-scale technology and impossible to view with the human eye. No-one yet knows the extent to which nanotechnology could transform our world, but it is generally acknowledged that the technology could be applied across a wide range of industries, and benefit quality of life. Raymond Oliver, Director of Science and Innovation at Cenamps – a centre of excellence in nano and small scale technologies, and a technical advisor to the Food Standards Agency, speculates as to how nanotechnology could transform the future of food packaging.

Over recent years, there has been increasing collaboration between the food industry, and science and technology, particularly early-stage R&D technology. It seems the industry is hungry to explore the possibilities that small scale technologies could offer. The possibilities are vast, particularly in the area of food packaging for increased safety, hygiene, freshness and consumer choice.

Moving advertisements on cereal packets made from paper-thin plastic electronic displays may seem futuristic, but the reality is that the technologies required to achieve this type of packaging already exist.

Plastic electronics, flexible displays, ultra-strong thin films, materials with enhanced thermal properties and more environmentally-sound plastics are already being researched and developed across the world, and the UK is at the forefront of this applied nanotechnological revolution. Centres such as the PETeC plastic electronics facility near Durham in North East England are helping to transform this sector and develop its commercial potential.

But while there is much activity occurring at the R&D stage to unite food packaging experts and scientists, the next crucial step will be to bring down the cost of the technology so that it becomes economically viable for an industry under constant financial and environmental pressures.

Food packaging is an area where nanotechnology can help to address real challenges within our society; spoilage and food wastage being a typical example.

Spoilage is one of the food industry’s main areas of wastage, and thus one of its most acute challenges. In the USA and Western Europe, wastage due to spoilage currently stands at €40 billion per annum – a massive figure. Reducing this wastage has the potential to transform the industry’s profitability, and nanotechnology has the potential to do just this, as well as improving food safety for consumers.

The use of ultra high-performance barrier coatings – often consisting of embedded nanomaterials – in food packaging, could improve products’ thermal stability, chemical resistance, oxygen and moisture ingress; greatly increasing the lifetime of a product.

Within the immediate future, such packaging is likely to be suitable only for more high quality, perishable foods (e.g. luxury meat and seafood products) as cost is currently prohibitive for cheaper products. This type of packaging could also incorporate smart sensors to operate a ‘traffic light’ system triggered by the condition of the food within it. For retailers, having a far more sophisticated and accurate method of knowing the condition of the food could considerably prolong the shelf life of products, reducing wastage, making more efficient shelf stacking and hence increasing profitability.

Furthermore, nanotechnology could revolutionise the merchandising involved in food packaging thanks to thin, flexible electronics that could ultimately make the products ‘respond’ to the customer. It may seem bizarre that a customer could walk down the tea and coffee aisle at the supermarket, and be identified by their favourite brand of coffee which then emits its aroma to entice them. But this smart packaging on goods does allow smart recognition, and is therefore not far off.

Such nanotechnology ‘fantasies’ are not as far fetched as may be imagined. Nanomaterials that can respond to light, touch or voice triggers could result in packaging becoming more integral to the product than ever before, no longer serving as a mere item for eventual disposal. ‘Intelligent nanomaterials’ could enable the creation of a ‘smart’ disposable coffee cup which, upon a voice trigger of “good morning”, for example, generates enough heat within the packaging unit to make a perfect cup of coffee.

Such an example would not be available in the immediate future, but the technologies behind it do currently exist.

RFID (radio frequency identification), or ‘smart tagging’ is an area which holds much more immediate scope for the food industry. Smart tagging can be used in conjunction with a retailer’s supply chain IT system; enabling better tracking of product deliveries, identifying the location of batches to within one metre, saving time and money, as well as detecting when food items are no longer safe to eat. Some retailers already use this technology to a limited extent in tracing the location of higher value products and to enable tracking of the condition of such items.

This technology could also ultimately make the shopping experience highly personalised to each consumer, and play a key role in product sales and marketing. Products could communicate with individual consumers through RFID tags on both the product and on a device held by the customer; for example jewellery or smart watches which contain RFID antenna. This could direct the customer to particular brands or products that they prefer, (informed through data held by the system), and suggest alternatives if a product has run out. It could also inform customers of any discounts or deals available, as well as calculating the payment required, processing this automatically as the customer is traced leaving the store.

The full potential of RFID will remain mainly untapped until some of the main barriers to widespread adoption, privacy and cost, can be overcome. RFID was trialled by large supermarket chains in the United States some years ago, but customer concerns over breach of privacy ensured it was short lived and ultimately unsuccessful. Until privacy issues can be appropriately addressed, it is unlikely that the industry will be able to fully exploit RFID’s potential. However, if the retailers can demonstrate that the technology will be deployed and any data used responsibly, the contribution of RFID, smart labels, sensors and holograms, all of which are driven by nanotechnology, will be enormous.

Health and safety is a further key concern at the moment which is halting the mainstream adoption of nanotechnology. This is a particularly pertinent issue within the food industry; with concerns expressed by some that nanoparticles could somehow enter the food chain.

As with any new technology, one of the key problems is a fear of the unknown. Because lifecycle studies have not yet been completed, robust results are not available and so the risk cannot be completely classified. These concerns were outlined in the recent Royal Society and Royal Academy of Engineering study in Nanoscience and Nanotechnologies. The biggest surrounded the use of ‘free in air’ technologies.

Studies into the health and safety implications of nanotechnology are at a relatively early stage, with independent industry bodies such as the Nanotechnology Industries Association (NIA) leading the way. Members of the NIA (including a company manufacturing the world’s first nanoparticle monitoring device) aim to create a clear single voice to represent the industry’s view, to interface with government and act as a source for consultation on regulation and standards while communicating the benefits of nanotechnologies to industry and the wider public. The NIA recognises the importance of assuring the industry of the safety of nanotechnology.

The findings of such research are likely to make nanotechnology increasingly acceptable to industries such as food packaging, as well as the general public. Until such time, innovations such as external nanomaterial barrier coatings are unlikely to appear in stores as concerns exist that particles may rub off on to food stuffs. Some other uses, however, are more likely to be increasingly adopted – RFID and polymer composite packaging materials such as Nanoclay being one example.

As demonstrated, many of the applications of nanotechnology within food packaging are at a very conceptual stage, and much more work needs to be done with scientists, investors, food retailers and government to enable the vision to become reality. But one thing is certain; the technology is not so far distant into the future as one may think; the technologies to make these concepts commercially viable, and acceptable to society, are already under way.

The fact is that nanotechnology holds very real and exciting benefits for the food industry. The key is to now address and overcome the uncertainty that exists; enabling these benefits to be fully exploited within the industry.

Reference

1. Royal Society and Royal Academy of Engineers report, ‘Nanoscience and Nanotechnologies: Opportunities and Uncertainties’, July 2004, ISBN 0854036040. This report can be found at www.royalsoc.ac.uk and at www.raeng.org.uk