Direct Determination Of Cu, Mn, Pb, And Zn In Beer By Thermospray Flame Furnace Atomic Absorption Spectrometry

In this work, thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) was employed for Cu, Mn, Pb, and Zn determination in beer without any sample digestion. The system was optimized and calibration was based on the analyte addition technique. A sample volume of 300 μl was introduced into the hot Ni tube at a flow-rate of 0.4 ml min-1 using 0.14 mol l -1 nitric acid solution or air as carrier. Different Brazilian beers were directly analyzed after ultrasonic degasification. Results were compared with those obtained by graphite furnace atomic absorption spectrometry (GFAAS). The detection limits obtained for Cu, Mn, Pb, and Zn in aqueous solution were 2.2, 18, 1.6, and 0.9 μg l-1, respectively. The relative standard deviations varied from 2.7% to 7.3% (n=8) for solutions containing the analytes in the 25-50 μg l-1 range. The concentration ranges obtained for analytes in beer samples were: Cu: 38.0-155 μg l-1; Mn: 110-348 μg l-1, Pb: 13.0-32.9 μg l-1, and Zn: 52.7-226 μg l-1. Results obtained by TS-FF-AAS and GFAAS were in agreement at a 95% confidence level. The proposed method is fast and simple, since sample digestion is not required and sensitivity can be improved without using expensive devices. The TS-FF-AAS presented suitable sensitivity for determination of Cu, Mn, Pb, and Zn in the quality control of a brewery. © 2005 Elsevier B.V. All rights reserved.605749753Matsushige, I., Oliveira, E., Determination of trace-elements in Brazilian beers by ICP-AES (1993) Food Chem., 47, pp. 205-207Matusiewicz, H., Kopras, M., Methods for improving the sensitivity in atom trapping flame atomic absorption spectrometry: Analytical scheme for the direct determination of trace elements in beer (1997) J. Anal. At. Spectrom., 12, pp. 1287-1291Moll, M.M., Food science and technology (1995) Handbook of Brewing, 64, pp. 133-156. , W.A. Hardwick Marcel Dekker New YorkLi, Y., Van Loon, J.C., Barefoot, R.R., Preconcentration of trace elements in potable liquids by means of a liquid membrane emulsion for flame atomic absorption determination (1993) Fresenius' J. Anal. Chem., 345, pp. 467-470Andersen, M.L., Skibsted, L.H., Electron spin resonance spin trapping identification of radicals formed during aerobic forced aging of beer (1998) J. Agric. Food Chem., 46, pp. 1272-1275Helin, T.R.M., Slaughter, J.C., Determination of metals in brewing materials by flameless atomic absorption spectrometry (1997) J. Inst. Brew., 83, pp. 15-16Svendsen, R., Lund, W., Speciation of Cu, Fe and Mn in beer using ion exchange separation and size-exclusion chromatography in combination with electrothermal atomic absorption spectrometry (2000) Analyst, 125, pp. 1933-1937Concon, J.M., (1988) Food Toxicology, , Marcel Dekker New YorkOnianwa, P.C., Adeyemo, A.O., Idowu, O.E., Ogabiela, E.E., Copper and zinc contents of Nigerian foods and estimates of the adult dietary intakes (2001) Food Chem., 72, p. 89Watson, C.A., (1994) Official and Standardized Methods of Analysis, pp. 688-689. , 3rd ed. Royal Society of Chemistry CambridgeBellido-Milla, D., Oñate-Jaén, A., Palacios-Santander, J.M., Palacios-Tejero, D., Hernández-Artiga, M.P., Beer digestions for metal determination by atomic spectrometry and residual organic matter (2004) Mikrochim. Acta, 144, pp. 183-190Bellido-Milla, D., Moreno-Perez, J.M., Hernández-Artiga, M.P., Differentiation and classification of beers with flame atomic spectrometry and molecular absorption spectrometry and sample preparation assisted by microwaves (2000) Spectrochim. Acta, Part B, 55, pp. 855-864Gáspár, A., Berndt, H., Thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS)-a simple method for trace element determination with microsamples in the μg l-1 concentration range (2000) Spectrochim. Acta, Part B, 55, pp. 587-597Davies, J., Berndt, H., Improvements in thermospray flame furnace atomic absorption spectrometry (2003) Anal. Chim. Acta, 479, pp. 215-223Pereira-Filho, E.R., Berndt, H., Arruda, M.A.Z., Simultaneous samples digestion and determination of Cd, Cu and Pb in biological samples using thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) with slurry sample introduction (2002) J. Anal. At. Spectrom., 17, pp. 1308-1315Nascentes, C.C., Arruda, M.A.Z., Nogueira, A.R.A., Nóbrega, J.A., Direct determination of Cu and Zn in fruit juices and bovine milk by thermospray flame furnace atomic absorption spectrometry (2004) Talanta, 64, pp. 912-917Welz, B., Sperling, M., (1999) Atomic Absorption Spectrometry, , 3rd ed. Wiley-VCH WeinheimAlcázar, A., Pablos, F., Martín, M.J., González, A.G., Multivariate characterisation of beers according to their mineral content (2002) Talanta, 57, pp. 45-5