The effects of germination and heating on bioactive properties, phenolic compounds and mineral contents of green gram seeds

Abstract

The moisture contents of non-germinated (control) and germinated (fresh germinated seed (wet)) green gram seeds varied between 7.62% (control) and 64.64% (fresh germinated seed (wet)). The antioxidant activity values of control, fresh germinated and heated samples were determined between 6.93% (conventional oven) and 22.90% (control) while total phenolic contents of green gram samples changed between 48.19 mg/100g (control) and 62.08 mg/100g (microwave oven). The total flavonoid contents of control, fresh germinated, and heated samples vary between 40.09 mg/100g (conventional oven) and 72.67 mg/100g (control). The highest carotenoid content was determined in fresh germinated green gram seeds. Antioxidant activity values, total flavonoid (except fresh germinated) and carotenoid contents of germinated and heated green gram seeds partly decreased compared to control seeds. Gallic acid, 3,4-dihydroxybenzoic acid, (+)-catechin, 1,2-dihydroxybenzene, syringic acid, caffeic acid and quercetin were the key phenolic constituents in both germinated and non-germinated (control) green gram seeds. Phosphorus content of control, fresh germinated gram seeds and germinated seeds heated by microwave, oven and infrared systems changed between 1315 mg/kg (fresh germinated seed (wet)) and 4942 mg/kg (microwave oven); K contents of green gram samples varied between 4342 mg/kg (fresh germinated seed (wet)) and 12,621 mg/kg (infrared oven).