Produção, caracterização e aplicação de filmes biodegradáveis de amido de mangarito (Xanthosoma sp.) incorporados com nanocelulose de eucalipto (Eucalyptus sp.) e pinus (Pinus sp.)

Abstract

Natural, biodegradable and widely available sources such as starch are excellent options to be used in the development of plastic films, presenting themselves as an alternative to the use of petrochemical derivatives, which contributes to the preservation of the environment. Mangarito is an unconventional amylaceous source, which can be used as a raw material that presents an appropriate biomatrix to support several bioactive substances when formulating biodegradable films. Eucalyptus and pine nanocellulose is also a highly available and renewable source, in addition to reinforcing and maintaining the biodegradability characteristics of the composites. In the present study, films formulated with mangarite starch were produced by the casting technique and incorporated with eucalyptus and pine nanocellulose at the following concentrations: 0%, 0.5%, 1% and 1.5% in 7g of polymer, using glycerol as plasticizer. Starch characterization was analyzed in amylose content: 24.58%; gelatinization enthalpy 7.8 J/g; relative crystallinity 38%. Regarding eucalyptus nanocellulose, particle size and surface charge were 14.34 nm and -38.70 mV, respectively, while for pine nanocellulose they were 18.99nm and -33.10 mV, respectively. The moisture susceptibility, water solubility and water vapor permeability of the films improved with the addition of reinforcement. Regarding the mechanical properties, the incorporation of nanofibers increased the tensile strength of the films. The mangarito starch showed a good response in the incorporation of both eucalyptus and pine nanocellulose due to the interactions between the polymer and the nanoparticle, results confirmed by the mechanical properties, susceptibility to moisture, water solubility and permeability to water vapor. For post-harvest conservation of carrots, nanofiber incorporated films showed the best results for maintaining fresh mass, soluble solids content and color preservation, contributing to extending the shelf life of the food.