Minerals and trace elements in Icelandic dairy products and meat

The aim of this study was to update the Icelandic Food Composition Database with respect to minerals (Ca, K, Mg, Na, and P) and trace elements (Cu, Fe, Hg, Se, and Zn) in frequently consumed agricultural products and to study the seasonal and geographical variation for these elements. Five food products typical for the Icelandic food basket were analysed: whole milk, fresh cheese (skyr), firm cheese (Gouda), lamb meat and minced beef together with skimmed milk, cream and whey. Concentrations of minerals and trace elements were determined by an inductively coupled plasma mass spectrometer (ICP-MS). Seasonal and geographical variation in whole milk was found only for selenium. Concentration of selenium in meat was variable and especially low for beef (1.4-9.6 μg/100 g fresh weight). Mercury was below the detection limit of 0.3 μg/100 g except for one sample of cheese. Skyr was rich in protein, calcium and phosphorus and retains almost all selenium in the skimmed milk used for its production. Skyr whey contains more calcium, magnesium, phosphorus and zinc than cheese whey. Skyr whey is a nutritious product, almost as rich in calcium, potassium and zinc as whole milk and could be used more by the Icelandic food industry.