Nutritional and Antinutritional Characteristics of Two Biofortified Bean Varieties Grown in Kenya

Abstract

Introduction: The introduction of biofortified bean varieties has brought attention to their potential as a source of high iron and zinc content. Objective: This study aimed to investigate the nutritional composition and antinutrient content of two biofortified bean varieties in Kenya, namely Angaza and Nyota. Methodology: The Proximate composition and mineral content were analyzed using standard AOAC procedures. HPLC analysis was used to determine the Phytic acid content, and the vanillin-HCL method to analyze tannins. Results:The two bean varieties had no statistically significant difference (P > 0.05) in carbohydrate content, with Nyota beans at 63.21% and Angaza beans at 61.67%. However, Nyota beans exhibited significantly higher protein content (19.97%) compared to Angaza beans (18.88%) with (P < 0.05). While Nyota beans had lower crude fiber (3.65%) compared to Angaza beans (4.78%), the variety showed significantly higher crude fat content (3.23%) than Angaza (1.55%). Both varieties had similar levels of crude ash, i.e., Nyota 3.29%, and Angaza 3.35%. Nyota beans demonstrated higher Iron and Zinc levels, i.e., 5.36 mg/100g and 2.77mg/100g respectively, compared to Angaza beans, 5.07 mg/100g Iron and 2.30 mg/100g Zinc. Nyota beans showed significantly lower levels of phytic acid, i.e., 2.53 mg/g and tannins 2.32 mg/g. Conclusions: The study found no significant statistical difference in the nutritional characteristics of the two varieties. However, the Nyota had higher protein, fat and mineral content, and lower levels of phytates and tannins. Thus, this study concludes that Nyota could have potential nutritional advantages over the Angaza variety.