Incorporation of waste orange peels extracts into PLA films

An important and hot-topic field in food packaging is the development of innovative active packaging, based on the incorporation of specific components, such as antioxidant and/or antimicrobial agents, able to modify the internal atmosphere or to be absorbed directly by the food, in order to prolong the product shelf-life. However, due to the increasing concerns of consumers about the plastics and the presence of synthetic chemical compounds in consumer goods, as well as, the importance of increasing environmental sustainability of the materials, has encouraged novel developments. This study is focused on the development of innovative, biodegradable and sustainable PLA-based active packaging solutions with the incorporation of natural antioxidant compounds recovered from agri-food wastes. An antioxidant extract was recovered through hydro-alcoholic extraction from waste orange peels, purified by resin absorption process and formulated as freeze-dried extract or spray-dried with pectin or cyclodextrins as carrier material. These three different formulations were incorporated into PLA films at different concentrations to investigate the influence of extract addition on polymer thermal stability and on colour and mechanical properties of films under accelerated light storage conditions.