Development and characterization of flexible film based on starch and passion fruit mesocarp flour with nanoparticles

Passion fruit mesocarp flour (MF) is a material of low-cost, because it can be produced from industrial processing of juices. The aim of this study was to develop flexible films based on MF, and to characterize their barrier, chemical, microscopic, thermal and mechanical properties, as well as to evaluate the rheological properties of the filmogenic solution used to produce them. The use of clay nanoparticles (NP) was also investigated. Films from MF were prepared by casting method, with glycerol as a plasticizer. The film forming solution of MF was more viscous than solutions of starch. The results of the contact angle values showed that films made from MF are more hydrophilic compared to starch, but there was no significant difference in water vapor permeability (WVP) and the thickness between these two different matrices. Regarding mechanical properties, the films made from MF proved to be tougher, stronger and less flexible. The formulation based on a mixture of MF and starch resulted in films less rigid and less resistant to tension, as compared to films based only on MF. The addition of NP did not influence the barrier properties, thermal and mechanical properties of films. Therefore, preparing films from MF, a cheap material, is a new alternative for taking waste from juice industries.

► The mesocarp passion fruit flour for flexible films was obtained by the casting technique. ► The influence of the addition of clay as nanoparticle was analyzed. ► The chemical, microscopic, thermal, mechanical and barrier properties of films were determined. ► The films with MF had properties similar to starch films and other biopolymers in the literature. ► MF films have potential use in foods.