With food costs rising just as fast as concerns about food waste, the arrival of a new form of food packaging that can extend the shelf life of perishable goods has come at the right time.
Every year, one third of all food produced is wasted; much of it going rotten. By improving food packaging household food bills can be lowered while at the same time reducing human environmental impact.
The breakthrough material that can achieve these goals is a thin polymer film that employs mineral nanotubes which slowly releases natural essential oils. These oils, extracted from plants such as thyme and oregano, have a natural antimicrobial effect inside the packaging, helping the food stay fresh for longer.
The film was developed by the company NanoPack, which received funding from the EU’s Horizon 2020 project to create its unique packaging, and can be used to package all manner of perishable goods, including meat, fish, vegetables, fruit, and dairy products. While details were publicised at the Active & Intelligent Packaging Industry Association (AIPIA) World Congress, held in November 2019, in Amsterdam.
The key to the new film is the application of halloysite nanotubes (HNTs) which have been chemically modified to allow for the efficient loading and controlled release of the oils. As the company’s website explains, “HNTs are considered to be one of the most promising natural nanomaterials. Their unique combination of properties include a tubular structure, high aspect ratio, low cost and abundant availability, good biocompatibility and high mechanical strength.”
Their role in the film is, “… to serve as nanoscale containers for encapsulation of antimicrobial molecules.” The nanotubes increase the thermal stability of the oils and allow them to be incorporated into a high-commodity polymer film. Once inside the packaging film, “The nanotubes slowly release the antimicrobial oils from the film into the headspace of the packaged food.” The EU’s scientific media body, CORDIS, explains, “This actively slows down oxidation, moisture changes and microbial growth.”
As a result, tests found that the packaging increased the saleability of fresh cherries by 40%, extended the shelf-life of cheese by 50%, and inhibited mould growth in bread by 3 weeks.
“The technology can be applied not only to food packaging, but also to a wide variety of cosmetic packaging. It presents a platform for many applications and can form the base of a large market worth hundreds of millions of euros, if not billions,” says Simon van Dam, a senior member of the NanoPack Project Executive. However, the nanotube film is not yet ready for market, with further testing required.
“We expect that it will require at least one to two years to finalize the development and obtain the required regulatory approvals. We are currently at a Technology Readiness Level of 7 out of 9, which is the stage needed to achieve a commercially ready technology,” van Dam adds.
The good news for the nanotechnology industry, is the positive feedback received from potential customers. Overall, consumers viewed the use of nanotubes in food packaging in a positive or neutral aspect, but interestingly, held a worse opinion over the use of essential oils, with survey participants seeing them “… in a negative tone (since they connect them with other non-food applications).”
In fact, the nanotubes are fixed inside the polymer and never come into contact with the food.
The survey also highlighted the conflicting interests between makers and buyers. Something that the company described as a, “trade-off between extending a product shelf-life (and what interests food producers) and freshness (what interests the consumers).”
Overall, those surveyed were positive about buying food packaged in a nanotube film as it aided product freshness and did not merely extend shelf life.
Crucially though, with more than 1.3 billion tonnes of food wasted every year, and countless people falling ill due to eating spoilt or contaminated food, the creation of a packaging that slows down or even stops the growth of microbes and bacteria is a much-needed development. While the use of nanotubes inside a polymer film may seem expensive and unnecessary, the value of the food that has to be thrown away actually makes smart packaging essential.