Back to nature: novel solutions to enhance food packaging sustainability

Commonly employed in food packaging, cellulosic materials are characterized by a biodegradable nature. Produced from renewable resources, paper-based materials can be evaluated as recyclable and biodegradable products. Nevertheless, the level of biodegradability of cellulose-based packaging depends on the substances and processes used to functionalize it. In order to use cellulosic materials in direct contact with food, indeed, paperpackaging industry concentrates its studies and researches on increasing barrier properties. Usually, cellulose-based packaging need to be functionalized through mechanical treatments, surface coatings, or by coupling paper with aluminum and polymeric films. These traditional surface treatments present disadvantages in terms of sustainability: they cause environmental problems due to materials recycling and recovering process. Papers used as primary food packaging could not be recycled, as food particles contaminate the paper recycling process, and should not be treated for composting because of the presence of non-biodegradable substances as coatings. For this reason, nowadays, the attention on minimizing environmental impact has prompted designers’ research to find more sustainable solutions for food pack. Teaching behaviour change on materials consumption in food packaging introduces to a wide range of design issues, including performance and aesthetic properties, sustainability, and food compatibility. Today, the challenge of food packaging industry is the development of new packaging materials, compatible with food, biodegradable or compostable, and realized with renewable resources. In the laboratories of the Department of Chemistry, Materials and Chemical Engineering “Giulio Natta” (at Politecnico di Milano), the good results obtained by testing some natural-based coatings, developed by the researchers of CIPACK (Interdepartmental Centre for Packaging) and applied to paperboard materials, let imagine novel scenarios of application in food packaging. Compostable food containers, made of cellulosic materials functionalized by the cited coatings, represent a sustainable alternative to pack, for example, ready-to-eat meals or fast food products. Moreover, this research opens to a new idea of food packaging: a system where packaging meets market criteria in terms of performance and cost, is designed to be functional and safe, is made using renewable resources, and at the end of its life cycle, as the food contained, could be degraded without leaving contaminants in the environment. The design and science-based approaches used in this study allow communicating a positive environmental vision for paper packaging used for food contact applications.