Bioavailability of Nutrients in a Fonio (Digitaria exilis) Ricebean (Vigna umbellata) Based Complementary Food

Abstract

Purpose: This study was carried out to assess the bioavailability of nutrients in a fonio/ricebean based complementary food. Methodology: Treated fonio (Digitaria exilis)/sprouted (72h) ricebean (Vigna umbellata) composite were processed into four complementary diets. FNBN-70:30:30:30(Fonio: ricebean: dried carrot: crayfish). A similar blend containing in addition 20g of milk (FNBP), a third blend that contained unsprouted and undehulled ricebean (FNBU) and the fourth that contained only fonio and ricebean (FNBM) were also formulated. These were analyzed for antinutrients, phytochemicals and viscosity using standard methods. Findings: There were slight variations in the trypsin inhibitor (1.16-1.78 Tiu/g), phytic (0.12-0.17%) and tannic acid (0.048-0.067%) contents of the samples. Cooking, soaking, sprouting and dehulling might have accounted for the observed low values of these antinutrients suggesting high bioavailability of the nutrients in the diets. The residual phytochemicals were equally low with sample FNBU having the highest values (alkaloid - 028%, flavonoid - 0.35%) and saponin 0.53%) among the samples which can be attributed to the non-sprouting and non-dehulling of the ricebean. The formulated diets showed low viscosities ranging from 84.21-85.77cP due probably to the thinning effect of amylases activated during sprouting. Decreased viscosity indicated increased nutrient density. The results showed high availability of the nutrients and low bulk/high nutrient density of the diets which showed suitability of the diets to argument nutrient and energy intake in children. Recommendation: Fonio/ricebean complementary food should substitute commercial complementary food.