Table 1 Composition of extruded rice formulations fortified with iron and zinc including relative iron solubility and visual scores.

Solubility values without a common script differ significantly (P < 0.05) using univariate general linear model with multiple comparisons Bonferroni correction. All rices were fortified with Fe (4 mg/g) except otherwise stated.

Fe compoundZn compoundSolubilizing agentMolar ratios
(Fe/Zn/solubilizing
agent)
Relative solubility*ΔE to basmati rice
FeSO481.6a ± 3.2214.6
FePP7.68b,c ± 0.905.09
ZnO1:0.713.6b,c ± 0.356.46
ZnSO41:0.74.35c ± 0.436.83
NaPP1:0.7:115.1b,d ± 0.845.59
NaPP1:0.7:1.537.0e ± 0.676.61
NaPP1:0.7:3.063.9f ± 6.156.74
NaPP and EDTA1:0.7:1:1112g,h ± 6.174.60
NaPP, EDTA, CA + TSC1:0.7:1:1:0.1:1.7102.7g ± 1.236.27
EDTA, CA1:0.7:1:0.199.2g ± 3.285.36
EDTA1:0.7:1108g ± 0.57.37
EDTA1:0.7:0.337.3d ± 0.355.94
EDTA, CA + TSC1:0.7:1:0.1:1.7118.9h ± 3.646.24
CA + TSC1:0.1:1.750.9i ± 3.97.55
CA + TSC + 20%1:0.12:2.059.9i ± 6.97.39
CA + TSC + 40%1:0.15:2.560.3i ± 5.067.91
FePPZnSO4NaFeEDTA1:0.7:0.0524.0d,l ± 2.488.34
ZnSO4NaFeEDTA1:0.7:0.1743.9e,i ± 1.668.55
FeOP17.3b,l ± 0.937.31
ZnSO41:0.710.4b,c ± 0.528.19
CA + TSC1:0.7:0.1:1.739.4e ± 1.038.74

*Solubility relative to unfortified basmati rice fortified with FeSO4 after cooking.

†Color differences relative to unfortified basmati rice. Rices with discoloration above ΔE values of ≥13 were distinguishable from unfortified basmati rice. In previous studies, rices with ΔE in the range of 5.1 to 6.7 compared to basmati rice were undistinguishable from unfortified basmati rice in triangle tests (20).

‡Fe (5 mg/g).