Several Factors Contribute to Dietary Content of Trace Elements

It is important to know the mineral element content of foods, which is affected by several factors, including soil contamination by pesticide or fertilizer, cooking conditions, and cooking utensils. We compared Zn, Mn and Cu intakes estimated using a food composition table (FCT) with values measured by atomic absorption spectrophotometry (AAS). The measured Mn content of dishes containing spinach was significantly higher than the corresponding FCT-based estimate. We studied the effect of home-based food preparation practices on the Zn, Mn and Cu content of dishes cooked with used utensils. The Mn content of foods cooked in a pan of aluminum alloy coated with fluoroplastic was higher than before cooking. The results suggest that thermolysis of fluorinated polymers, such as the commercial polymer Teflon, can cause Mn migration from aluminum alloy into foods. Our studies show that food preparation using the techniques available in the home may be responsible for decrease or increase in mineral content. Further studies are needed to ascertain the effects.