. A team of scientists from Nanyang Technological University (NTU Singapore), and Harvard T.H. The Chan School of Public Health in the USA has created a smart food packaging material that kills harmful microbes. It could extend fresh fruit’s shelf life by up to two days.
The waterproof packaging for food is made from a corn protein called Zein, starch, and other naturally derived biopolymers. It also contains a mix of natural antimicrobial chemicals. Citric acid is also common in citrus fruits and oil from thyme.
Lab experiments have shown that when exposed to humidity or enzymes of harmful bacteria, the packaging fibres release natural antimicrobial substances, killing common bacteria that can contaminate food.
The packaging is designed to release minimal amounts of antimicrobial substances only when there is additional humidity or bacteria. This allows the packaging to withstand multiple exposures and lasts for many months.
The compounds are effective in fighting bacteria on food products and on packaging. It can be used to make a wide range of products including ready-to eat foods, raw meats, fruits, vegetables, and other processed foods.
In an experiment strawberries wrapped in plastic packaging lasted seven days before developing mold, as opposed to their counterparts kept in conventional fruit plastic boxes that lasted only four days.
The invention was made possible by the collaboration of scientists from NTU-Harvard T. H. Chan School of Public Health Initiative for Sustainable Nanotechnology. (NTU–Harvard SusNano) brings together researchers from Harvard Chan School and NTU to develop non-toxic, environmentally-safe nanomaterials.
The University is working to promote sustainable food technology solutions. This strategy aligns with the NTU 2025 strategic plans, which seeks to create sustainable solutions for some of humanity’s most pressing grand challenges.
Professor Mary Chan (Director of NTU’s Centre of Antimicrobial Bioengineering), who led the project, stated: “This invention could serve as a better choice for packaging in food industry because it has demonstrated superior antimicrobial properties in combating a myriad of food related bacteria and fungi which could be harmful to people. This packaging can be used on a variety of produce, including meats, vegetables, and fruits. Smart release of antimicrobials only in the presence of bacteria or high humidity provides protection only when it is needed, minimising the need for chemicals and protecting the natural composition of the foods being packaged. “
Professor Philip Demokritou is an Adjunct Professor in Environmental Health at Harvard Chan School and also the Director of Nanotechnology and Nanotoxicology Center and co-director of NTU Harvard Initiative on Sustainable Nanotechnology. He said that food safety and waste are a major societal problem of our time with immense economic and public health consequences. The development of non-toxic, biodegradable food packaging materials is one of the best ways to improve food safety and reduce food spoilage. In this study, we used nature-derived compounds including biopolymers, non-toxic solvents, and nature-inspired antimicrobials and develop scalable systems to synthesise smart antimicrobial materials which can be used not only to enhance food safety and quality but also to eliminate the harm to the environmen