Effects of blending ratios variation on micronutrient compositions and phytate/minerals molar ratios of dabi teff-field pea based novel composite complementary flours

Abstract

Mixtures of multiple grains at varied ratios can provide multiple and higher micronutrients than a single grain. Thus, this research was aimed at examining the effect of blending ratios variation on micro-compositions and phytate/minerals molar ratios of pre-processed local dabi teff-field pea based novel composite complementary flours. Inductively Coupled Plasma-Optical Emission Spectrometry was used to determine dietary minerals. Nutrisurvey software was employed to define ranges of the mixture components and they were constrained at 20–35% for dabi teff, 0–30% field pea and 5–20% maize, while the remaining were set constant at 25% barley, 15% oats and 5% linseed. Design-Expert ® software version 11, D-optimal was used to generate eleven experimental blends and to examine the effects of blending ratio variation on the responses. Mean mineral contents were significantly different (P < 0.05) among the blends (as affected by component ratios variation) and ranged from 24.01–31.58 mg/100 g for iron, 73.46 -78.81 mg/100 g for calcium, and 2.33–2.61 mg/100 g for zinc contents. The phytate/minerals molar ratios were significantly different among the blends except phytate/calcium molar ratio (Ph:Ca), ranged from 0.232–0.344 for phytate/iron molar ratio (Ph:Fe), 0.067–0.085 for (Ph:Ca), 3.356–4.18 for phytate/zinc molar ratio (Ph:Zn) and 6.457–7.943 for phytate by calcium to zinc molar ratio (Ph*Ca:Zn). A linear model was significant (P < 0.05) and adequate to describe variations in iron, zinc, Ph:Fe, Ph:Zn and Ph*Ca:Zn. There was a remarkably linear increase in iron and calcium contents with an increased dabi teff ratio in the blends accompanied by a significant decrease (P < 0.05) in phytate/minerals molar ratios. The findings showed that increasing dabi teff ratio in the blends notably increased iron content with reduced Ph:Fe molar ratio, providing the bases for developing iron-dense novel composite complementary flour with improved iron bioavailability to combat iron deficiency anemia among children. Graphical Abstract: (Figure presented.)