Impact of short-term germination on dehulling efficiency, enzymatic activities, and chemical composition of mung bean seeds (Vigna radiata L.)

Mung beans are promising for protein ingredient production, but their benefits are hindered by potential antinutritional factors and coloring compounds in the hull, resulting in darker-colored products. To address this issue, this study aims to identify a germination period that enhances dehulling efficiency while minimizing mass losses and chemical alterations. Mung bean seeds were soaked overnight and germinated in the dark for 4, 8, 12, 24, 32, and 48 h, with the effects on dehulling efficiency, enzymatic activities, and chemical composition, including antinutritional factors, examined.

After 48 h of germination, a substantial increase in enzyme activities was observed: lipolytic activities increased by 644 %, amylolytic activities by 200 %, and polyphenol oxidase activity by 280 %. A decline in protein (21.02–25.77 %), starch (41.83–56.65 %), and fat (0.35–1.03 %) content was detectable after 48 h of germination. SDS-PAGE analysis revealed a reduction in globulins and structural changes with prolonged germination. Total phenolic content was particularly reduced by 20 % due to dehulling. Short-term germination within 12 to 24 h was found to be an effective strategy to facilitate dehulling of mung bean seeds while reducing antinutritional factors and preserving their chemical composition, thus improving their potential as a high-quality raw material for plant-based foods.