Functional Properties’ Comparison of different Sustainable Packaging designed for Meat Products

Packaged cured meat products are very sensitive to microbial growth, fat oxidation, and discoloration, especially caused by residual oxygen and water vapour concentration in the headspace of the package. Therefore, packaging plays a crucial role to prevent chemical, enzymatic and physical spoilage thanks to barrier properties effective for humidity, gases (O2, CO2, odours), and UV radiation. The most widely used packaging materials for cured meat products are plastics, including polyethylene terephthalate (PET) together with multi-layered packaging composed mainly of polyethylene (PE) and ethylene-vinyl-alcohol (EVOH). Plastic materials, characterized by a low cost and lightweight, have also excellent processing performances such as mechanical strength, low permeability, transparency, and heat sealability. However, multi-layered plastic packaging does not comply with the fundamentals of the circular economy, since they are assembled with non-renewable sources, i.e. fossil fuels and natural gases, and the recycling process is still an open issue due to the difficulties whit the layers’ separation. Therefore, the huge production and utilization of such materials further contribute to environmental issues such as exhaustion of natural resources, pollution of terrestrial and marine ecosystems, and global warming. Therefore, thanks to recent European environmental policies and the growing public awareness regarding environmental challenges, the scientific community and companies must invest time and energy to develop suitable and effective sustainable packaging materials capable of ensuring the same food quality and safety standards as traditional packaging materials. Based on this information, this Ph.D. project aims to study, optimize, and validate packaging materials designed for cured meat products in a modified protective atmosphere (MAP), with a higher degree of sustainability and circularity degree. Potential solutions could be the mono plastic materials and bio-based plastics that are both fully recycled and bio-based and compostable materials such as bioplastics (PLA, PHA, PBS). Nevertheless, to our knowledge, only a few scientific papers are available regarding sustainable packaging for cured meat products in MAP conditions, and up to now, the most sustainable packaging applications in the market are limited to the use of paper assembled with plastic layers. For this purpose, the first part of this Doctoral thesis is focused on the comparison between sustainable types of packaging and a standard plastic film already applied for cured meat products. The materials that will be analysed are the following: standard multi-layered PET-PE/EVOH/PE, mono-PET, mono-PE, PHA, and PLA film. This investigation aims to compare the different functional properties required by cured meat products stored in MAP, i.e., seal and tensile strength, elongation break resistance, thermal behaviour, colour and opacity, oxygen and water vapor permeability, and wettability of the film. These results will allow exploring the properties of the materials from a deeper and more technical point of view, in order to individuate the most effective sustainable packaging materials.