Activities included preparatory work, 4 pilots and activities to increase project impact. Preparatory work included functionalisation of HNTs inner and outer surfaces to maximize loading and controlled release of antimicrobial payloads. Additionally, antimicrobial activity of 12 EOs and their combinations was tested against relevant food microorganisms. Specifically, a combination of carvacrol, thymol and cinnamaldehyde showed very promising and synergic antimicrobial activity against E. coli, Listeria innocua, and Penicillium commune (representing Gram positive bacteria, Gram negative bacteria and mould, respectively) and different concentrations were tested in the pilots for achieving the highest antimicrobial efficacy at low concentrations.
Successful upscaling of the loading process was performed in 3 types of HNTs: pristine (un- processed) and 2 types of functionalised HNTs – etched and silanized. The loading process imparts enhanced thermal stability by at least 30C to the EOs, allowing for their melt compounding with polymers at high manufacturing temperatures.
Successful melt compounding of 3 types of loaded HNTs from Pilot I, with different polymers was performed. Masterbatches from Pilot II were characterized to assess processability and antimicrobial activity. Processing various compounds as part of pilot III was done using existing facilities at industrial pilot plants. Moreover, films were produced in large and small industrial facilities, CFlex and Tommen, respectively, demonstrating transferability of the technology to large and small production plants. Many configurations of active NanoPack films – different numbers of layers and various EOs content, were tested in different food systems, including dairy products, bakery goods, meat, fish and fresh produce (cherries).
Safety assessment of HNTs use was performed both as occupational hazard and exposure assessment for personnel working in product manufacturing and for consumers eating NanoPack packaged foods. Safety and toxicity studies in mice revealed that HNTs do not cause cytotoxicity however the etched HNTs (e-HNTS) were associated with lung inflammation. Work with HNTs during the large-scale application of pristine and etched HNTs is feasible, if the recommended precautions are taken. Ecotoxicological studies investigated the effects of pristine and e-HNTS in the aquatic environment. Tests with D. magna showed no inhibition of reproduction, for pristine HNTs but e-HNTS extended the period to first brood and reduced the number of living offspring. The results prompted the decision to proceed only with pristine HNTs.
Migration studies measured HNTs and EOs movement from the films and into foods. It was concluded that HNTs do not migrate out of the film.
Dossiers for HNTs and the 3 potent EOs po were prepared for submission to EFSA. This was done after establishing how an active packaging should gain food-contact approval in the EU.
Life cycle assessment studies were performed on an ongoing basis including Environmental life cycle assessment, Life cycle cost (LCC) and Social life cycle assessment (s-LCA). Results showed that the HNTs do not contribute significantly to the overall potential environmental impacts. LCC showed, the final cost per m2 of plastic film is aligned with the average cost of a multilayer film on the market (range to be 3 to 5 €/kg). The s-LCC, showed that the highest risks were identified at the resources’ extraction stage, where more developing countries were involved.
Innovation management continued throughout the project and commercial feasibility studies concluded. Consumer and retailer acceptance studies were carried out on a global level in Europe and China and showed promising results of consumers and retailer acceptance of the NanoPack technology. Exploitation opportunities beyond the project were explored between industrial partners with some research partners expressing interest to collaborate.
Communication of results to a wide range of key stakeholder groups was done via a variety of targeted tools and channels including a website, leaflet, roll-ups, articles in trade media, newsletters, media engagement, webinars, scientific papers, videos, social media, and presence at events. Seven scientific publications were produced with 2 more in preparation based on NanoPack work. Training workshops on using HNTs as carriers of anti-microbial EOs in food packaging were conducted and the final event held in association with the International AIPIA packaging event where the project was extensively showcased, the consortium members spoke and conducted sessions as well as hosted a booth.
