Proximate and heavy metal analysis of grasshopper species consumed in Katsina State

Abstract

The study was conducted with the aim of determining some nutrients and metal concentrations in grasshopper samples consumed in Katsina State. The experimental group samples were purchased from Batsari, Jibia and Mai’adua markets while the control sample was obtained from the Biological Garden, Federal College of Education, Katsina. Samples were authenticated at the Entomology Unit, Usman Danfodiyo University, Sokoto and found to be the same species. Samples were prepared and analysed using standard procedures. Sample A (control) had the lowest moisture content (5.667%), ash (9.833%) and crude fibre (10.333%). It recorded the highest crude protein content (57.330%), crude lipid (10.667%) and carbohydrate (6.170%). Sample C had the highest moisture (9.500%), ash (15.167%) and crude fibre (14.500%). It had the lowest crude protein content (48.857%) and carbohydrate (2.810%). The concentration of all the metals are within the WHO permissible limits except for Mn, Cd and Pb in Sample D, and Pb in sample C which exceeds the limits. ANOVA indicated no significant difference in metal and nutrient concentrations within the sampling locations (P= 0.07>0.05 for metals and P=1>0.05 for nutrients). A significant difference was however indicated between the concentrations in the different samples (P=0.04<0.05 for metals and P= 0.000<0.05 for nutrients). From the result obtained, it can be concluded that grasshopper can be a good source of nutrients although there is need for continuous monitoring of metal concentrations. The location and preservation methods may also affect the concentrations of both nutrients and metals.