Benefits, concerns with nanotechnology packaging
Article By Carol Zweep Published January 31, 2025
Article Source: https://www.foodincanada.com/opinions/benefits-concerns-with-nanotechnology-packaging159394/
There has been a strong focus in the packaging industry on sustainability, food quality and safety. Sustainable developments have targeted recyclable packaging that support the circular economy of plastics. Polymer nanocomposite can provide enhanced barrier and mechanical strength to plastic packaging without interfering with the recyclability of the material. Packaging with polymer nanocomposites can avoid the use of multi-polymer structures as well as reducing the weight of the package. Antimicrobial and antioxidant nanostructures can also be incorporated in the package.
Applications
Nanomaterials are tiny particles ranging from 1 to 100 nm in size and can be made from organic or inorganic materials. Polymer nanocomposites are formed by dispersing an inert, nanoscale filler (2-8 per cent) within the polymer. The most common filler materials include clay, silica, carbon, graphene, starch, cellulose, and chitosan. The tortuous path created by nanofillers changes the diffusion rate, thereby improving the barrier of the material. It is also thought that nanoparticles improve the barrier properties by creating changes in the polymer matrix. Uniform distribution of the fillers within the polymer matrix is a challenge with this technology.
The industry is moving toward bio-based packaging, but these materials generally have inferior properties (poor barrier, brittleness, low heat distortion) compared to conventional fossil-based plastics. Nanobiopolymer packaging overcomes these limitations by offering better barrier performance, increased mechanical strength, and improved thermal stability.
Nanocomposites with antimicrobial and antioxidant properties have the potential to prolong the shelf life of the food products by suppressing their enzymatic, oxidative, and microbial spoilage. Metal and metal oxide nanoparticles, such as silver, titanium, copper, zinc, zinc oxide, magnesium oxide, titanium oxide, have antimicrobial properties. Adding antioxidants can deter oxidation of fat and proteins, thus maintaining product quality. Use of synthetic antioxidants such as butylated hydroxy-toluene, have been extensively used in food packaging. The use of natural antioxidant compounds (tocopherols, polyphenols, and essential oils) has gained increased interest.
Food safety and regulatory concern
Studies have shown that nanomaterials can migrate from packaging into food, presenting concerns about consumer exposure and safety. Migration rate from packaging materials depends on factors such as the food composition, contact time and temperature. Additionally, nanomaterials can have different properties compared to the macro-sized counterpart. There are few specific regulations on nanotechnology packaging, which also differs from country to country. Deeper understanding of nanostructure toxicology is still evolving.
Future developments
There is ongoing research in new areas of nanotechnology use. Development is underway for sensor and indicator technology that conveys information to the consumer about the freshness of the packaged food, providing time and temperature data, and detecting pathogenic micro-organisms and harmful chemical agents. Nanotechnology for packaging is expanding to encompass release of value-added substances into the packaged food such as nutraceuticals, vitamins and nutrients.
Although there is huge potential for nanotechnology in food packaging, this technology has not become mainstream. Commercial advances in this industry have not been made due to consumer wariness as well as regulatory and safety concerns, high development and manufacturing costs.
Carol Zweep is the packaging researcher at Conestoga Food Research & Innovation Lab, Conestoga College.
This column was originally published in the Nov./Dec. 2024 issue of Food in Canada.