Physicochemical and techno-functional characterization of soluble proteins extracted by ultrasound from the cricket Acheta domesticus

The growing interest in using insects for human consumption is due to their numerous benefits. Insects offer efficient protein generation, rapid growth rates, and high nutritional value. The objective of this work was to evaluate the physicochemical and techno-functional properties of the different soluble protein fractions of the cricket <i>Acheta domesticus</i> using various methods: grinding (CF), defatting (DCF), alkalinization (SPA), and ultrasound-assisted extraction (SPS). CF, DCF, SPA, and SPS were used as extenders in food models and compared with a control group prepared with meat and a commercial soy protein (SPI). Defatting increased the protein content (52 %) in CF, improving digestibility, while the SPS extraction method improved solid recovery (40.46 %), protein recovery (41.94 %), total protein content (53.85 %), and digestibility (53.7 %) compared to SPA. Proteins exhibited pH-dependent solubility, with higher solubility at pH 12-13 and an isoelectric point of 4.5. In techno-functional properties, SPS had the highest water/oil retention capacity (2.8 g/g, 3.49 g/g), foam formation (386.66 %), and emulsifying stability (32.96 m²/g). CF showed no foam formation, although defatting (DCF) improved foam formation (8.33 %) and emulsifying stability (6.23 m²/g). Heat coagulation was higher for CF and DCF (30.58 % and 30.33 % respectively). All meat models with SPA and SPS showed high elasticity and cohesiveness but low hardness, gumminess, and chewiness. The model prepared with 15 % SPS reduced cooking losses (0.91 %) and total expressible fluid separation (1 %), improved water retention capacity (83.02 %), and increased total soluble protein content (5.32 mg/mL). The ultrasound-assisted extraction method proved to be an efficient way to obtain soluble proteins from <i>Acheta domesticus</i> with techno-functional properties suitable for use as a food additive or meat extender.