A new eco-friendly packaging system incorporating lignocellulose nanofibres from agri-food residues applied to fresh-cut lettuce

Abstract

The present work explored the design and testing, at pilot scale, of a new food packaging prototype, based on biodegradable polymers and eco-materials obtained from agri-food residues using an environmentally friendly process for its application in vegetable products. For this purpose, several film formulations were developed with combinations of polylactic acid (PLA) and polybutylene adipate-co-terephthalate (Ecoflex®), incorporating different proportions of lignocellulose nanofibres (LCNF) obtained from an enzymatic pre-treatment of wheat straw waste. The production of the LCNF-reinforced packaging (i.e., bag) was carried out at pilot scale. The assessment of its physico-chemical properties showed an improvement of the optical properties, water vapour permeability and antioxidant capacity as compared to a fresh-cut lettuce commercial package. The improvement was more evident in formulations of 70:30 PLA:Ecoflex® with 0.5 and 1% LCNF. The application of the new formulated packaging in a product of fresh-cut lettuce was also tested by simulating real manufacturing, packaging and storage conditions at pilot scale. Results demonstrated levels of microbiological and sensory quality comparable to those observed in the commercial formulation. This work demonstrates that the development of packaging systems obtained from biodegradable materials and valorised with plant biomass from agri-food activity could be the basis for the creation of a more environmentally sustainable food packaging strategy.