Beverages, trace analysis

Pichon, V., A.I. Krasnova, and M.C. Hennion. 2004. Development and characterization of an immunoaf-finity solid-phase-extraction sorbent for trace analysis of propanil and related phenylurea herbicides in environmental waters and in beverages. Chromatographia 60 S221-S226. 

The most important analytical techniques which are used in multielement trace analysis are ICP-MS, atomic absorption spectrometry (AAS) and ICP atomic emission spectrometry (AES). NAA is applied as reference method in order to establish certibed values. The regular atomic spectrometry update on clinical and biological materials, foods and beverages (ASU review) gives an overview of the recent developments in elemental analysis of food and beverages [81]. 

ICP-MS is a multi-element technique suitable for the analysis of liquid samples, which provides higher selectivity and detection power and LoDs lower than other multi-element techniques, such as ICP-AES. These characteristics make ICP-MS an excellent tool for the detailed characterization of the elemental composition of beverages. In this context, ICP-MS was the technique selected for the determination of 31 trace elements in wine at concentrations ranging from 0.1 to 0.5 ng ml-1 [82]. Samples were diluted 1 + 1 and it was investigated whether a matrix effect derived from the presence of ethanol could be overcome by using a microconcentric nebulizer with membrane desolvation. The authors compared their results with those obtained using a conventional Meinhard nebulizer and concluded that the matrix effect observed could only be minimized by using an internal standard with the Meinhard nebulizer, but not with the other one. 

F. L. Fricke, Trace element analysis of food and beverages by atomic absorption spectrometry. Prog. Anal. Atom. Spectrosc., 2 (1979), 185-286. 

Yasabura, A., Kawada, K. and Sbibamoto, T. gas Cbromatograpbic/mass spectrometric method for analysis of trace carbonyl compounds in foods and beverages. J. Agric. Food Chem. 46, 2664-2670 (1998). 

Aqueous samples such as drinking water, surface water, and waste water but also beverages and urine samples, should always be acidified with mineral acids for stabilization purposes immediately after collection. This is especially true for the prevention of desorption processes during sampling and storage of samples in the course of trace metal analysis. Acidification reduces the tendency for ions to be adsorbed onto active sites at the surface of the containment vessel, and it also inhibits bacterial growth [9]). Glacial acetic acid and... 

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