The Effect of Chemical and Enzymatic Modification on Starch Hydrogels Isolated From Vigna subterranea (Bambara Groundnut)

ABSTRACT Native starch is known to possess mechanical properties and is readily available; however, it exhibits limitations, such as low dimensional stability and poor gel content. In this study, starch from Vigna subterranea genotypes (B3 and B4) and potato starch were modified through chemical and enzymatic processes using hydrogen peroxide and α‐amylase, respectively. Samples were characterized using SEM, DSC, and FTIR, and functional properties were assessed, including amylose content, water‐binding capacity (WBC), syneresis, swelling power (SP), and the water solubility index (WSI). Textural tests were conducted on the formed gels to determine viscosity and hardness. Electron microscopy analysis showed both chemical and enzymatic modifications affecting the morphology of starch granules, and FTIR spectra identified oxidation via the C═O stretch, with varying degrees of enzymatic hydrolysis indicated by band intensities at 1020, 1156, and 1080 cm −1 . Mechanical properties indicated that native starch produced significantly harder gels than modified samples. Enzymatically modified (EM) potato starch gel achieved the highest SP, while hydrogen peroxide modification resulted in a higher WSI, and enzymatic modification yielded higher values than native starches for WBC. Findings from this study show the potential of enzymatic modification as the preferred method for developing hydrogels, owing to its softer gel formation, enhanced WBC, and controlled action.