Formulation of weaning food from yellow maize (Zea mays L.) and red millet (Eleusine coracana L.), enriched with pretreated African locust beans (Parkia biglobosa Jacq.) flour

This work aimed to formulate adequate weaning food with acceptable protein and mineral contents from yellow maize and red millet enriched with pretreated Parkia biglobosa (PB). PB seeds were boiled to facilitate dehulling. The dehulled seeds were divided into different portions, which were respectively fermented (3 and 6 days), oven roasted (175 °C for 20 and 40 min), and microwaved (450 W for 15 and 30 min). Maize and millet flours used as control samples, were respectively mixed (1:1 w/w) with pretreated PB seed flours, to constitute fourteen formulations. These formulations were analyzed for their proximate, mineral compositions, physical and functional properties, total phenolic content and antioxidant activity. There was significant increase in protein, carbohydrate and lipid contents for formulations made with PB roasted in oven (175 °C, 40 min) and in microwave (450 W, 30 min). Protein content of all formulated infant flours was above 15 g/100 g DW recommended value for infant complementary foods. The highest energy value (485.09 kcal) was obtained with the formula maize and P. biglobosa oven roasted at 175 °C for 40 min. The formulated flours have the required values of K, P, Ca, Mg and Na as recommended by the WHO. Formulations made with pre-fermented PB exhibited the highest swelling capacity (173.43%), water holding capacity (230.85 %), total phenolic content (48.32 mg GAE/g) and antioxidant activity (95.78%). Their least gelation concentration values decreased compared to the sample added with untreated PB. With a maximum value of 10.25, titratable acidity increased with roasting time while the pH value decreased. Porosity decreased with processing time. The value of the Hausner ratio (HR < 1.4) revealed that the formulated flours have good flowability behavior. Based on the obtained result, pretreated dehulled PB seeds could be recommended in the enrichment of complementary food made from maize and millet.