Determination of the mineral content of spices by ICP-OES

Abstract

Spices represent all edible plant parts used for food flavouring or colouring including fruits, roots, seeds, peels or vegetable substances. The objective of this study was to determine the elemental composition (Ag, Al, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, In, K, Li, Mg, Mn, Na, Ni, Pb, Sr, Tl and Zn) of selected spices available in the local markets on Serbian territory. The presence of heavy metals in spices is of particular importance because this could result in the accumulation of these elements in human organs, which further might cause different health problems. The analysed spice samples were curcuma, star anise, cinnamon, ginger, coriander, cardamom, sesame, black pepper, chilli and curry. The preparation of the samples was done by wet digestion. The concentrations of elements after digestion were determined by Inductively Coupled Plasma ‒ Optical Emission Spectrometry (ICP-OES). In the group of spices macroelements, from all examined elements the calcium concentration was the highest (182.25 ‒ 3968.79 mg/kg), about 83%. From the heavy metals group, aluminium was most present in the range of 0.0-10.78 mg/kg, while cadmium and nickel were detected in almost negligible amounts.