Impact of High-Pressure-Assisted Extraction of Alphitobius diaperinus and Tenebrio molitor on Protein Characteristics

Abstract

The effectiveness of high pressure-assisted extraction (HPAE) in improving insect protein extraction and functionality was studied. Defatted insect powders of Tenebrio molitor and Alphitobius diaperinus were pressure treated at 100–300 MPa for 5 min at 25 °C. Protein content, molecular weight distribution (MWD) of protein fractions, emulsifying activity (EA), and modifications in the secondary structure of the proteins were assessed for the different fractions. In comparison to control, HPAE at 100, 250, and 300 MPa enhanced protein extraction by approximately 18% for both insect species. A 22% increase in protein extraction was observed for A. diaperinus at 200 MPa compared to the control. A clear decrease in EA was noted for both T. molitor and A. diaperinus proteins extracted at 150, 200, 250, and 300 MPa. The MWD analysis indicated that HPEA increased the intensity of protein bands between 10–20 kDa and around 37 kDa for both insect species. This study demonstrates the potential of high pressure to not only enhance protein extraction by up to 22% but also to modify the emulsifying activity of insect proteins.