Determinação de teores de metais pesados em açúcares com diferentes solventes

Abstract

Nine samples of sugars or sweeteners classified as crystal, demerara, brown, aspartame and sucralose were obtained from supermarkets in the Campo Mourão - Paraná region and subjected to analysis of Flame Atomic Absotption Spectrometry (FAAS) for determination of heavy metal content and by Near-Infrared Spectroscopy (IV-NIR) for to evaluate possible differentiations between sugars. For the FAAS analysis, the sugars were prepared in four types of water as solvent, being: deionized water, deionized with nitric acid, the water treatment plant of the city of Campo Mourão and the Federal Technological University of Paraná Campo Mourão campus. For comparison criteria, the samples were submitted to a digestion process by incineration in a muffle oven. The solutions obtained in both steps were analyzed for heavy metals lead, copper, aluminum and iron. The results were negative for lead and copper in all conditions, whereas for aluminum and iron the contents varied according to the samples of sugars and solvents used. Infrared spectroscopy was used as a possible faster alternative for the characterization of sugars, where the samples were prepared and conditioned in transparent plastic bags to obtain the spectra which in turn were processed by data. The results suggest that bonds present at specific wavelengths are responsible for the differentiation of sugars and that in this way they can be monitored in order to investigate the effect of the mineral composition.