Combining Cupuassu (Theobroma grandiflorum) Puree, Pectin, and Chitosan Nanoparticles into Novel Edible Films for Food Packaging Applications.

Every year, the residues generated by the disposal of packaging materials produced from fossil fuels have been growing, denoting a major environmental problem that can be mitigated by the development of biodegradable materials from natural polymers, particularly edible films. This work aimed at the development of pectin films added by cupuassu puree and chitosan nanoparticles and to evaluate the improvement of the physical-mechanical performance of the composite films. The nanostructures displayed an average size of 110 nm and a zeta potential of approximately +40 mV. The films were produced by casting, and they exhibited manageability, homogeneity, and continuity. Based upon the mechanical analysis of maximum stress and elongation, it was concluded that the nanoparticles functioned as fillers, increasing the toughness of the pectin films. Water vapor permeability assays demonstrated that the nanostructured films containing cupuassu exhibited improved barrier properties. The glass transition temperature of the films was not strongly affected by the addition of nanoparticles. Conversely, the initial degradation temperature decreased with the addition of nanoparticles and cupuassu puree. The outcomes of this research pave a new route for the development of nonconventional food packaging materials.

Effect of chitosan nanoparticles and pectin content on mechanical properties and water vapor permeability of banana puree films.

UNLABELLED: Puree prepared from over-ripe peeled bananas was used as raw material for films processing in a laboratory padder. Pectin and glycerol as plasticizer were added in small concentrations and chitosan nanoparticles (88.79 ± 0.42 nm medium size) incorporated at 0.2% (dry weight basis) as reinforcement material. The mechanical properties, water vapor transmission, thermal stability, and scanning electron microscopy of fractured film surfaces were characterized. Both pectin and glycerol demonstrated an important role in promoting elongation and film handability as was expected. The incorporation of nanoparticles promoted noticeable improvement of the mechanical properties and acted in reducing the water vapor permeation rate, by 21% for films processed with pectin and up to 38% for films processed without pectin, when compared to the control (puree films with no pectin and nanoparticles additions). Microscopic observation revealed a denser matrix when nanoparticles are incorporated into the films. PRACTICAL APPLICATION: The development of films from fruit purees head to a new strategy for plastic processing from natural resources. The over-ripe or even waste banana can be adequately prepared for batch films processed with reasonable mechanical and barrier properties, suitable for applications in the food segment. The addition of small fractions of chitosan nanoparticles, form nanocomposites enhancing mechanical and thermal stability broadening potential film applications.