Trace metal concentrations in three pastry products prepared from root and tuber and cereal crops composite flours

Abstract

The concentrations of Arsenic (As), Lead (Pb), Mercury (Hg), Copper (Cu), Iron (Fe), and Zinc (Zn) in doughnuts, cookies, and bread prepared from root and tuber and cereal crops composite flours were quantitatively measured by Atomic Absorption Spectrophotometry. Varying concentrations of trace metals were identified in three pastry products. Concentration of Hg was <0.01 mg/kg wet weight in all three pastry products. The As levels in all three pastry products ranged between <0.01 and 0.03 mg/kg. Concentrations of Pb was <0.01–0.05 mg/kg, far lesser than 10 mg/kg recommended limit by World Health Organization (WHO). The highest Fe level of 66.3 mg/kg occurred in cookies made from millet composite flour, whereas the lowest value of 10.4 mg/kg was in doughnuts made from water yam composite flour. Concentrations of Cu (1.03–1.83 mg/kg) and Zn (5.49–13.72 mg/kg) were lower than the tolerance limit of 40 mg/kg set by WHO. The presence of trace metals at varying concentrations in all three pastry products demonstrates the need for observing food safety controls in sourcing for raw materials and during processing of flours from root and tuber and cereal crops