Contribuição do corante amarelo de tartrazina como agente modificador da estrutura do amido de milho

Abstract

The objective of this study was to investigate ways to promote modifications in the structure of corn starch using pH 4 and 5, adding the tartrazine yellow dye as a chromophore compound in the concentration of 0.3%.The samples were exposed to ultraviolet radiation from sunlight for 24 hours and different times and reaction temperatures in the forced circulation air oven, in an attempt to give this other capabilities different from the in natura starch. A 4x3 factorial design was used, where the reaction time of the samples with the dye had 4 levels and the reaction temperature factor with the dye 3 levels, totaling 12 tests at each pH. Analyzes of centesimal composition, pH and acidity, viscosity, scanning electron microscopy (SEM), infrared spectroscopy, X-ray diffraction (XRD), expansion analysis and specific volume were performed. The data of the samples were analyzed statistically by the program Statistica10, the graphs of viscosity and DrX were elaborated in Oring Pro 8.The analysis of the samples of corn starch in the scanning electron microscope (SEM) presented some changes in the structure of the granules submitted to the treatments, suggesting that few alterations were induced by the treatment that the material was submitted. This fact was confirmed by the results of the infrared spectrophotometry analyzes, through which few changes were observed in the stretching of the bands corresponding to the functional groups of the treated starch when compared to the standard sample. However, it was observed that, biscuits produced from the modified samples in this experiment, although they did not expand satisfactorily, showed signs of resistance to retrogradation. Thus, this suggests that the treatment interfered positively in the total retrogradation capacity of the starch, a fact that may be relevant in the application on an industrial scale in the production of foods derived from corn starch.