Effects of germination on the physicochemical, thermal, in vitro protein digestibility, Antinutrients, and antioxidant properties of sorghum flour

Abstract

SummaryThe present study investigates the impact of germination (72 h) on physicochemical, protein solubility, in vitro protein digestibility, antinutrient, antioxidant, and structural properties of sorghum flour. Germination resulted in a reduction of crude protein, fat, fibre, and ash. However, it significantly improved the DPPH (58.42%–69.44%), total phenolic content (1.31–3.58 mg GAE g−1), and total flavonoid content (57.66–80.16 mg QE g−1). Germination also increased in vitro protein digestibility (50.12%–75.52%) and Fe2+ chelating activity (11.18%–48.06%), while reducing antinutrients such as phytic acid (176 to 86 mg/100 g) and tannin (3.53–2.16 mg/100 g). Structural analyses (XRD and FTIR) revealed modifications in crystalline and molecular structures, while scanning electron microscopy showed disrupted starch granules in germinated flour. These findings suggest that germination enhances the functional and nutritional properties of sorghum flour, making it more suitable for various applications in food products.