Caracterização dos rizomas filhos e da fécula do mangarito (Xanthosoma mafaffa Schott) e elaboração de filmes biodegradáveis

Abstract

In this work, were determined the physical and chemical properties of the comels of mangarito starch and some properties of biodegradable films from starch and glycerol. Were determined the mass and the major and minor diameters and chemical composition of the comels. Were also determined the chemical composition and calorific value of the extracted starch, and its thermal and pasting properties. The morphology and size of their granules were analyzed. The films were prepared using the casting technique by varying the amount of glycerol and the mass of filmogenic solution according to a central composite factorial design. From the obtained films were studied the appearance, thickness, permeability and solubility. Was applied an analysis of variance for a second degree polynomial model and the desirability function for the optimization. The average weight of comels was 3.5 g with major and minor diameters of 23 and 15 μm respectively, being mainly constituted of granules with rounded 12.5 μm in diameter. The starch paste presented good stability under heat and mechanical stirring and great tendency to retrogradation. Considering as desirable the factors low thickness and permeability and high solubility, films made with 10% glycerol and 24.73 g of filmogenic solution would comply better to these characteristics.