Determination of Selenium in Liquid Dietetic Sweeteners by GF AAS

Graphite furnace atomic absorption spectrometry was used to determine Se in liquid dietetic sweeteners. The optimized pyrolysis and atomization temperatures were 1,100 and 1,900 A degrees C, respectively. Since there is not a certified reference material for sweeteners, addition and recovery experiments were used to evaluate the accuracy of the proposed method. The obtained recovery values were between 94% and 108%, without the use of a mineralization step, except for the aspartame sweeteners. The instrument limit of detection was 0.02 A mu g L-1 and the relative standard deviations were below 6.4%. The methods studied were applied to different kinds of sweeteners having cyclamate-saccharine, cyclamate-saccharine-stevioside, or aspartame. The analyte concentrations were compared with the limits established for inorganic species in foods by ANVISA (Brazilian Agency for Health and Safety). The results indicate that there is a huge variation in the concentration of selenium in the 27 samples studied and that the values can be considered relatively high for the sweeteners with cyclamate/saccharine and cyclamate/saccharine/stevioside contents.