Embalagens alimentícias eco-friendly com nanofibras de celulose bacteriana e óxido de carbono amorfo hidratado: obtenção, processamento e propriedades dos materiais

Abstract

This research aimed to develop sustainable eco-friendly packaging using bacterial cellulose nanofibrils obtained from agro-industrial waste and hydrated amorphous carbon oxide of plant origin. The research was carried out in three stages: (i) obtaining and characterizing bacterial cellulose nanofibrils (BCN) from alternative sources of fermentable carbon from agro-industrial waste from soursop (Annona muricata L.) and genipap (Genipa americana L.) from the tropical regions of the Brazilian Amazon, through a static fermentation route3; (ii) investigation of the processing of a hydrated amorphous carbon oxide suspension of plant origin (HSACO) via ultrasonic cavitation in a hydroalcoholic medium, optimizing the conditions for obtaining stable nanostructured dispersions with functional and biological safety properties 4; and (iii) development of eco-friendly packaging with HSACO and BCN, through the discontinuous casting method, as a viable and strategic solution in the economic, environmental, and social spheres5. Two distinct polymer matrices were used: protein (gelatin) and synthetic (polyvinyl alcohol PVA)6. In stage I, the alternative sources proved to be viable in the formation of BCN, being ecological, sustainable, and economical solutions due to their bioavailability in the production of biomaterials7. The BCNs had a crystallinity index greater than 75%, formed by a network of micro, submicro, and nanostructures of random shape8. In stage II, ultrasonic cavitation in HSACO proved to be efficient, forming a stable, conductive, polydisperse $(\text{PDI}\le3.0)$ suspension at 30%W for 120 min9. Structural organization, such as graphene oxide and reduced graphene oxide, with isolated nanostructures <100 nm10. Additionally, no mortality or anatomical changes were observed in the acute toxicity test Danio rerio (zebrafish)11. Finally, in stage III, the incorporation of HSACO and BCN from genipap into polymer matrices (gelatin and PVA) resulted in packaging with excellent UV radiation barrier properties, maintaining high levels of transparency12. In addition, the mechanical properties were improved in terms of toughness, tensile strength, and elasticity of the materials with the incorporation of 5.0% $(\text{v/v})$ BCN13. These results demonstrate that the developed packaging is technologically viable14. The incorporation of HSACO and BCN, derived from sustainable sources, as reinforcing nanoadditives confirms the significant scientific, technological, and innovative potential of this approach for developing new materials for the food industry.