Z. V. Gaile, V. Rudovica, J. Burlakovs, M. Klavins, E. Priedite
Tuesday 6 August 2013 by Libadmin2013

References: 13th SGEM GeoConference on Ecology, Economics, Education And Legislation, www.sgem.org, SGEM2013 Conference Proceedings, ISBN 978-619-7105-04-9 / ISSN 1314-2704, June 16-22, 2013, Vol. 1, 49 - 56 pp


Food and drinking water are the main sources of major and trace elements in human nutrition. Quantitative analysis of food samples is important not only for detection of essential elements but also for assessment of potential food contaminants such as As, Al, Cd, Cr, Pb, Ni. Among different methodologies that can be used for determination of elements in samples of food and beverages, such methods as atomic absorption or emission spectrometry (AAS/AES), inductively coupled plasma mass spectrometry (ICP-MS) and total reflection X-ray fluorescence spectrometry (TXRF) are mostly applied. The aim of the current study is to evaluate the relevance of sample pre-treatment procedures and accuracy of applied analytical methodologies for quantitative analysis of major and trace elements in samples of food and beverages. Pre-treatment of samples usually is needed; however, in some cases direct sample analysis can be done. Within the current study pre-treatment procedures of food and beverages samples were examined. Some samples (e.g., apple juice, wine) were comparatively analysed with and without sample pre-treatment. Among applied sample pre-treatment procedures, wet digestion by concentrated nitric acid was assessed as the most appropriate. Certified reference materials (e.g., apple powder, lichen, red wine) were used for detection of precision and accuracy of applied analytical methods. After sample pre-treatment, quantitative element content was measured by AAS/AES, TXRF and ICP-MS. It was important to evaluate the performance of TXRF as this methodology allows direct sample analysis. It was found out that precision and accuracy of the results obtained by TXRF is acceptable in cases when there is a necessity to generate quick analysis for the tentative detection of quantities of major and trace elements in food samples, particularly, in samples that can be analyzed directly (e.g., juice, wine). The most accurate quantitative analysis of elements content in food and beverages can be done by AAS/AES and ICP-MS which allow the obtaining of results at necessary threshold levels.

Keywords: quantitative analysis, major and trace elements, food, beverages, AAS, TXRF, ICP-MS