Modulation of functional properties, molecular structural and thermal stability of Indian teff (Eragrostis tef)...

This study investigates the physicochemical, functional, structural and thermal properties of protein isolates from Indian teff (Eragrostis tef) as influenced by germination at different durations (8, 16, and 24 h). Progressive germination led to a significant (p ≤ 0.05) enhancement in protein content (82.91% to 90.14%). Functional properties improved with germination, with water holding capacity increasing from 2.88 to 3.25 g/g and oil holding capacity from 2.27 to 3.13 g/g. Germination increased particle size and altered zeta potential, suggesting modifications in surface charge. SDS-PAGE revealed partial depolymerization of protein subunits, suggesting changes in aggregation behavior during germination. XRD patterns showed decreased peak intensity without positional shifts, suggesting reduced molecular order in germinated samples. IR spectra revealed conformational changes characterized by reduced β-sheet and increased β-turn content. Thermal analyses (DSC and TGA) showed improved stability at 8 h of germination (Td 81.6 °C; ΔH 164.4 J/g), followed by a decline at 24 h (Td 79.2 °C; ΔH 129.5 J/g), reflecting protein restructuring and partial degradation. SEM revealed increased surface porosity and structural loosening with germination. Principal component analysis further confirmed clear discrimination among samples, highlighting germination-induced transitions that improve the functional and processing potential of teff protein isolates.