Most materials currently used for food packaging are non-degradable, generating environmental problems.
Several biopolymers have been exploited to develop materials for eco-friendly food packaging.
However, the use of biopolymers has been limited because of their usually poor mechanical and barrier
properties, which may be improved by adding reinforcing compounds (fillers), forming composites. Most
reinforced materials present poor matrix–filler interactions, which tend to improve with decreasing filler
dimensions. The use of fillers with at least one nanoscale dimension (nanoparticles) produces nanocomposites.
Nanoparticles have proportionally larger surface area than their microscale counterparts, which
favors the filler–matrix interactions and the performance of the resulting material. Besides nanoreinforcements,
nanoparticles can have other functions when added to a polymer, such as antimicrobial
activity, enzyme immobilization, biosensing, etc. The main kinds of nanoparticles which have been studied
for use in food packaging systems are overviewed, as well as their effects and applications.