Optimizing the nutrient content and consumer acceptability of a white maize based composite flour formulation with vitamin a biofortified maize and iron rich beans

Abstract

Micronutrient deficiencies are still an important public health problem globally. About 40% of children aged 6–59 months are affected by anemia and 29% of children in the same age category suffer from Vitamin A deficiency globally. Biofortification is a cost-effective strategy in reducing micronutrient deficiencies and other forms of malnutrition. However, the success of any biofortification program largely depends on the consumer acceptability of biofortified crops within the target population. The main objective of this study therefore was to optimize the nutrient content and consumer acceptability of a white maize based composite flour formulation with vitamin A biofortified maize and iron rich beans. The proximate, ant nutrient composition and functional properties of the optimized flour were determined and compared with the maize based composite flour and one other commercial composite flour. Design Expert 2018 (Version 12) was used to generate 30 treatments representing different combinations of the different composite components. Response surface methodology using the D-optimal mixture design was adapted to design the experiment for optimization. The levels of inclusion for six independent variables were: 50 – 60 g biofortified maize flour, 15 – 20g high iron biofortified bean flour, 5 – 10g sesame flour, 5 – 10g soy flour and 5g each of wheat and sorghum flours. The response variables were overall acceptability, vitamin A, phytate and iron concentration. An optimal formulation of the composite flour was achieved with 57.9% biofortified maize, 17.1% iron rich bean flour, 5.0% sesame flour, 10.0% soy bean flour, 5.0% wheat flour and 5.0% sorghum flour. The optimal values for the responses were 1.58 µg/g Retinol activity equivalents of beta carotene, 6.0 mg/100 g of iron, 54.20 mg/100 g of phytate and an overall consumer acceptability score of 7.1. The protein (11.9 g/100 g), ash (2.8 g/100 g) and fat (5.6 g/100 g) contents of the optimized flour were significantly (p<0.05) higher than those for the white maize based composite flour. The anti-nutrient (tannin, phytate and oxalate) contents of the optimized composite flour blend were significantly ((p<0.05) lower than those for the white maize based composite flour. The optimized composite flour also had better functional properties compared to the white maize- based composite. Therefore, vitamin A biofortified maize can effectively replace white maize in complementary foods, enhancing micronutrient intake and addressing protein-energy malnutrition in children under 5 years.