Protein Quality, Beta-Carotene Contents, and Sensory Properties of Maize-Based Snack Enriched with African Yam Bean Seed Flour

Maize-based snacks are deficient in protein and vitamin A, which can be enriched using value-added processes to incorporate appropriate food ingredients such as African yam bean seed flour (AYBSF). African yam bean seed is a nutrient-dense, but underutilised crop. This study was designed to investigate some quality attributes of maize-based snacks enriched with AYBSF, and its application as functional food ingredients. The maize variety containing carotenoids was chosen to produce maize flour (MF), and enriched with AYBSF to produce snacks (Kokoro) at various substituted ratios MF/AYBSF (100:0, 80:20, 70:30 and 60:40) using Box Behnken experimental design. Carotenoid contents, trypsin inhibitor activity (TIA), in vivo protein quality and sensory attributes of the samples were determined. The carotenoids contents of the flour blends showed a significant (p<0.05) decrease in lutein (7.20-5.11µg/g), zeaxanthin (10.36-6.06 µg/g), β-cryptoxanthin (1.83-1.13 µg/g), α-carotene (0.36-0.21 µg/g) and β-carotene (1.84-0.92 µg/g) as the percentage of AYBSF increased in the flour blends. The TIA was not detected in 100% MF, but TIA increased in the flour blends with the increasing percentage of AYBSF, which reduced significantly during the processing of the flour blends into Kokoro. The protein availability in Kokoro depicted no significant (p>0.05) difference from the standard casein diet, which implies that the developed snack compares well with standard casein. This study shows that enriching maize-based snacks with AYBSF is a good prospect which could be useful in advising nutritional programs, especially for school-aged children. Kokoro enriched with AYBSF could be preferred to the commonly consumed carbohydrate-based snacks.