Elemental Analysis of Selected Spices Used in Nigerian Cooking Obtained from Abia State Markets

Spices are integral to Nigerian culinary culture and are consumed in substantial daily quantities, yet the elemental composition of commonly used spices, particularly those sourced from local markets in South East Nigeria, has received limited systematic investigation. This study performed elemental analysis of six spices widely used in cooking in Abia State, namely uziza leaves, utazi, ogiri, uda seeds, ohu leaves, and efirin, purchased from three markets in Umuahia. Samples were prepared by dry ashing and dissolution in dilute nitric acid. Elemental concentrations of calcium, magnesium, potassium, sodium, iron, manganese, zinc, copper, chromium, lead, and cadmium were measured by atomic absorption spectrophotometry. Potassium was the most abundant macronutrient across all spices, with uziza leaves reaching 14,240 mg/kg on a dry weight basis. Calcium and magnesium were also present in nutritionally significant amounts. Iron concentrations were highest in ogiri at 1,238 mg/kg. Zinc ranged from 42 to 186 mg/kg. The toxic elements lead and cadmium were detected in all spices, with lead ranging from 0.8 to 4.2 mg/kg and cadmium from 0.04 to 0.32 mg/kg. These levels, while low, contribute to overall dietary heavy metal intake, which warrants monitoring given the frequency of spice consumption. The findings provide nutritional data for common South East Nigerian spices and raise questions about contaminant sources requiring further investigation.

Keywords: elemental analysis, spices, heavy metals, Abia State, Nigerian cuisine