Cassava starch-processing residue utilization for packaging development

Abstract

The starch-based film development has been extensively studied since, in general, it is possible to obtain transparent, non-toxic, odorless, good gas barrier, biodegradable, and tasteless samples. However, world hunger-related problems are a reality and the use of starches, a recognized carbohydrate source, in the packaging industry should be avoided. Thus, the use of different residual starchy can minimize the costs of production, promoting the development of innovative biomaterials, eliminating the competition with the food chain. The objective of the present work was to evaluate the impact of the cassava starch (CS) substitution by gelatinized starch (GS), a residue generated in the sieving step of starch processing, verifying possible changes in the final material characteristics. The raw materials characterization includes determination of amylose and moisture contents, centesimal composition, particle size distribution, and thermal analysis. After casting solution and drying processes, the samples were evaluated regarding the visual macroscopic and microscopic aspects showing continuous and homogeneous structure. The results were related to the physicochemical and mechanical properties. The GS addition promoted a decrease in the tensile strength (3.3 ± 0.1 MPa to 1.2 ± 0.3 MPa) and elastic modulus (52 ± 13 MPa to 10 ± 3 MPa) values, while the elongation percentage (160 ± 30% to 212 ± 14%) values seem to have not been so affected. It can be seen a high potential for the use of agro-industrial residues containing starch in bioplastic production.

Keywords: Biodegradability; Cassava starch residue; Casting; Gelatinized starch; Residual starchy source.