Nutritional Composition and Glycemic Index Analyses of Vitamin A-biofortified Maize in Healthy Subjects

Besides being a veritable tool for easing the problem of vitamin A deficiency (VAD), this study sought to explore another potential health benefit of vitamin A-biofortified maize (VABM). In the present study, the nutritional composition and glycemic index (GI) of tuwo masara (a nonfermented maize-based dumpling), made from VABM and the indigenous white maize (IWM) genotype, were evaluated. VABM showed significantly (<0.05) lower fat (4.38 ± 0.46%) and crude protein (6.58 ± 0.13%) but higher crude fiber (5.29 ± 0.0%) contents compared to 5.22 ± 0.25% crude fat, 7.28 ± 0.11% crude protein, and 4.69 ± 0.00% crude fiber in the IWM. The phytic acid content in the IWM (2.77 mg/100 g) was 39% higher than the level (2.0 ± 0.04 mg/100 g) in VABM. The major provitamin A carotenoid in the VABM were lutein (7.37 ± 0.52 μg/g), zeaxanthin (1.65 ± 0.01 μg/g), cryptoxanthin (1.29 ± 0.02 μg/g), and all-trans-β-carotene (0.83 ± 0.02 μg/g), while the IWM contained only lutein (1.52 ± 0.32 μg/g). The total carotene concentration, 12.74 ± 1.13 μg/g dry weight in the VABM, was over eight times higher than that observed for the IWM, 1.52 ± 0.32 μg/g dry weight. The VABM tuwo masara showed a significantly lower GI value (70.3%) compared to the IWM tuwo masara (87.7%). Data obtained from the study further attest to the positive nutritional and health benefits of VABM.