Impact of gamma irradiation on the structural, functional and physicochemical properties of pea protein isolate
Madina Aitmagambetova, Rong Bai, Jing Xi, Aidana Rakhimova, Wu DingAbstract
BACKGROUND
The properties of pea protein isolate (PPI), comprising a sustainable plant‐derived protein for which the full functional potential in complex food matrices remains unrealized as a result of inherent limitations in food applications, are investigated in this work under gamma ( γ ) irradiation (0–10 kGy). The study used non‐thermal physical treatment, namely γ irradiation, using ionizing radiation from a 60 Co source, which causes controlled structural rearrangements in macromolecules.
RESULTS
Fourier transform infrared spectroscopy deconvolution revealed irradiation‐induced changes: partial unfolding of secondary structures ( α ‐helix/ β ‐sheet), whereas scanning electron microscopy showed fragmented morphology (4–8 kGy) and aggregated clusters. Functional properties peaked at 8 kGy with solubility, emulsifying activity and water/oil‐holding capacity, whereas 10 kGy enhanced emulsion stability but reduced solubility because of disulfide cross‐linking.
CONCLUSION
This study establishes 8 kGy as the critical threshold for balancing structural flexibility and functionality of PPI, providing a non‐thermal strategy for tailoring plant proteins in next‐generation foods. Physicochemical studies linked these changes to disulphide bond breaking, free sulfhydryl dynamics and fluorophore exposure. These results highlight γ irradiation as a flexible approach to modify PPI activity, hence balancing structural changes with particular dietary applications. © 2026 Society of Chemical Industry.