Desenvolvimento e caracterização de filmes comestíveis de fécula de mangarito (Xanthosoma mafaffa Schott), e sua aplicação na cobertura em frutos de jabuticaba

Abstract

In the present report it was studied the extraction of the starch of the comels from the “mangarito” with the objective of using it as eating covers in the postharvest conservation of the “jabuticaba” fruit. The quality of the covering was tested, at first, through the permeability (Pva) and solubility of the biodegradable films and also through the physicochemical parameters of the fruits, determined by the time of conservation. The filmogenic solutions were prepared from the “mangarito” starch (CF) and plasticizer glycerol (CG) in concentrations that varied in the CF from 1,44; 2,5 and 3,56g, and CG 12,93; 20 and 27,70%. The biodegradable films (FBs) prepared were characterized by the permeability to water steam (Pva) and solubility in water. The eating covers were prepared from the filmogenic solutions with 2,5% of (CF) and different concentrations of (CG) (10,0;20,0 and 30,0%). The experimental lineation used was the central composed, of the star kind, with five repetitions in the central spot and four axials, to verify the effect of the percentage of glycerol (GLI) in the filmogenic film and the selection of the best biofilms for further use in the postharvest through the methodology of response surface. For the postharvest conservation, the lineation was entirely randomized disposed in a 4x5 factorial scheme, with five repetitions, in which the first factor corresponded to the treatments: 0 (control), 10,0; 20,0 e 30,0% of glycerol, and the second to the time of storage (0, 1, 2, 3 and 4 days). The increase of glycerol concentration in the covers collaborated to the increment of the water steam permeation and solubility of the films. The SF proved to be little hydrophilic, once the starch, even being hydrophilic, was added in a relatively low concentration. The covers were not efficient in the control of the physicochemical changes of the “jabuticaba” fruit in the control of the loss of mass, pH and the relation between the total soluble solid and the total titratable acidity, not being observed a significant difference between the revested fruit with the different covers and those with no packing.