Researchers develop edible packaging from agro-food industry waste

Potato and quince peels, non-standard fruit and crustacean peels are the "raw material"

A team from the University of Coimbra (UC), with the collaboration of the Escola Superior Agrária de Coimbra (ESAC), developed a set of edible packaging from different residues from the agri-food and fisheries sector, a sustainable alternative to plastic.

In practice, these edible packages are films obtained from residues of different foods, namely potato and quince peels, non-standard fruit and crustacean peels, which, in addition to coating the food, prolong its shelf life from the supermarket, can also be eaten.

The packaging developed by researchers Marisa Gaspar, Mara Braga and Patrícia Almeida Coimbra, from the Research Center for Chemical Processes and Forest Products Engineering (CIEPQPF), from the Faculty of Science and Technology of the University of Coimbra (FCTUC), were designed essentially to coat fruits, vegetables and cheeses, incorporating in its matrix bioactive/nutraceutical compounds, such as antioxidants and probiotics, with potential beneficial effects on health.

We can imagine, for example, cooking broccoli or asparagus without removing the packaging, since the film that surrounds them is made up of natural nutrients with health benefits.

«We produce different compositions of films, using the residues almost entirely, which contain compounds with different properties. For example, potato skin has more starch and quince skin has more pectin, that is, we have two structural polymeric materials that, combined, will generate a simple film, without complex processing», explain Marisa Gaspar, Mara Braga and Patrícia Almeida Coimbra.

However, before being able to obtain films/coatings either in film or spray form (applied in liquid and dry phase in food), the team, which brought together several research groups from UC and ESAC, had to overcome several phases.

«The biggest challenge is to find the ideal materials so that the formulations have the desired characteristics. Therefore, it was necessary to study the films from a physical point of view, such as the mechanical properties, in order to serve as packaging/coating; study the bioactive properties of the films, that is, whether some compounds present health benefits when ingested; evaluate the reactions when different compounds are added; microbiological and sensory analysis of selected films; and evaluate the compatibility of the food with the edible system produced», summarize the three FCTUC researchers.

Marisa Gaspar, Mara Braga and Patrícia Almeida Coimbra consider that the solution proposed by their team can be “very advantageous for both the industry and the consumer. It is an approach centered on the circular economy. Not only does it increase the shelf life of the product, it also prevents waste, reduces the production of plastic waste, a serious environmental problem, and generates a new product that adds a nutritious addition to the food», they conclude.

Initiated in 2018, within the scope of the “MultiBiorefinery” project, funded by COMPETE 2020, this research was recently awarded a prize of 20 euros for the “Interdisciplinary Research Seed Projects – Santander UC” program, awarded to multidisciplinary teams led by young researchers at the University of Coimbra.

It was also awarded in the LL2FRESH ideas contest, which aims to seek new packaging solutions, food treatment methods and state-of-the-art additives.

As part of this project, a scientific article was published in the journal Food Packaging and Shelf Life, available here.


Author: Cristina Pinto – Press Office – University of Coimbra – Science Communication