A methodological approach to the assessment of trace elements in milk and dairy products

Abstract

A detailed protocol was applied to the study and quantification of Al, Ba, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Pt, Sr and Zn in raw cow's milk and dairy products. The investigation was prompted by the paucity of data available on minor and trace elements in such matrices, despite their importance in nutrition or in food contamination. As a part of an overall monitoring programme, a study was thus undertaken with the following goals: (i) actual measurement of the concentration of the aforesaid elements in milk and related products; (ii) identification of possible correlations between animal feeding, time of year of sample collection, environmental condition and levels of elements in raw cow's milk; and (iii) evaluation of the influence of the manufacturing process on the concentration ranges of certain health-related elements in milk products. Quantitative determinations were carried out by means of inductively-coupled plasma atomic emission spectrometry (ICP-AES). The results obtained show considerable differences among the levels of trace elements in raw milk and those in derived products. This provides evidence of the fact that manufacturing processes play a key role in the distribution of trace elements.