Desenvolvimento de embalagem biodegradável com potencial bioativo à base de amido de mandioca.

Abstract

The environmental impact generated by the improper disposal of packaging based on synthetic polymers encourages studies for the development of packaging from biodegradable polymers. The present work aims to develop and characterize biodegradable films with bioactive potential, produced with cassava starch, glycerol containing different amounts of cassava cortex extract. The films were produced by casting. The starch (2.1 g) and water (100 ml) were mixed and subjected to heating for starch gelatinization, then the glycerol was added and incorporated into the gelatinized starch. Subsequently, the solution was placed in silicone molds and subjected to drying in an oven with air circulation, at a temperature of 35ºC for 24h. The films were characterized according to their physical properties (water content, solubility, water vapor permeability, color and thickness), physicochemical properties (total phenolic compounds and antioxidant activity), mechanical properties (Young's modulus, elongation at break and tensile strength), morphological properties (surface and cross sectional SEM, structural properties (FT-IR), functional properties (migration test) and biodegradability. The amount of phenolic compounds in the films increased from 61.30 mg EAG/100g to 187.03 mg EAG/100g, as the amount of extract increased. The antioxidant activity of the films by the FRAP method increased from 1.42 to 19.62 mmol Fe2+/kg, from 4.53 to 12.91 mmol Trolox/kg by the ABTS method and from 3.05 to 4.95 mmol Trolox/kg by the DPPH method. Thickness, solubility, water vapor permeability and color were influenced by the increase in the amount of extract in the composition of the films. The Young's modulus and elongations at break were also influenced by the amount of extract. The migration test was performed using three simulants (water, acetic acid and alcohol) and at two temperatures (28ºC and 4ºC). The films presented different migration behavior of phenolic compounds in the three simulants used (aqueous medium, acid medium and alcoholic medium) and an influence of temperature on the migration of phenolic compounds was observed. The films showed mass loss over the six weeks proven, although this was not enough time for their complete biodegradation. Thus, it was found that cassava starch films with the addition of cassava cortex extract are good options for replacing conventional packaging made from materials from non-renewable sources.