Acheta domesticus protein extract as functional ingredient: physicochemical, thermal and rheological properties

This study investigates the techno-functional, thermal, and rheological properties of a protein extract obtained from defatted Acheta domesticus flour via thermally aided alkaline extraction coupled with isoelectric precipitation, aiming to evaluate its potential in diverse food applications. The resulting cricket protein extract (CPE) exhibited high protein content (85.65 %), and a marked pH-dependent solubility profile over the pH range 3–10, with a minimum near pH 4 and a value of 59.69 % at neutral pH. The extract also displayed favourable techno-functional properties, reaching a foaming capacity of 170 % and a foam stability of 92.59 % at pH 7. Emulsifying behaviour was likewise pH-dependent, with high emulsion stability maintained across the investigated pH range. Differential scanning calorimetry revealed a single endothermic denaturation peak near 55 °C (ΔH =2.01 J g− 1), indicating moderate thermal stability and suggesting the retention of organized protein domains. Rheological analysis showed concentration-dependent shear thinning behaviour (n <1) and weak-gel viscoelasticity after thermal treatment, with G′ higher than G″ and tan δ <0.3. Network strength increased with concentration, indicating the ability of the extract to develop structured systems under processing-relevant conditions. Collectively, these findings indicate that A. domesticus protein extract is a functional, thermally responsive ingredient, showing performance within ranges reported for plant-based proteins and potential for use in food systems requiring water binding, interfacial stabilization, and elastic response, including meat analogue and related protein-based products.