Physicochemical and antioxidant properties of proteins extracted from the body, wings, and legs of Gryllus bimaculatus

Abstract Edible insects are increasingly recognized as sustainable protein sources; however, appendages such as wings and legs are often discarded during processing. This study compared proteins extracted from the whole, body, wings, and legs of Gryllus bimaculatus to evaluate their structural, functional, and antioxidant properties. Legs showed the highest protein content (20.88%), while wings had the highest ash content (9.81%). Wing proteins exhibited the greatest surface hydrophobicity (20.75%) and the highest molecular mass (approx. 69 kDa), while body proteins formed smaller particles (approx. 142 nm) with a more negative zeta potential (−32.77 mV), indicating enhanced colloidal stability. Wings and leg proteins maintained high foam stability (>90% at 60 min), while body proteins demonstrated superior emulsifying capacity. Antioxidant assays revealed strong activity for wing proteins (DPPH approx. 64.6%; ABTS approx. 81.1%) and significant intracellular ROS reduction, approx. 55–65% relative to the H 2 O 2 control. Amino acid profiling revealed that wings were enriched in Gly, Ala, Val and Pro, with measurable levels of Tyr and His, suggesting hydrophobic peptide–mediated interfacial scavenging rather than classical aromatic-driven mechanisms. Overall, wings and legs – typically treated as by-products – contain functional and bioactive proteins with promising potential for food and nutraceutical applications, supporting resource-efficient utilisation of insects as sustainable protein sources.