Properties of insect protein concentrate and potential application in seasoned rice noodles

In this study, we extracted proteins from four edible insect species ( Acheta domesticus, Gryllus bimaculatus, Holotrichea sp., and Gryllotalpa orientalis), then evaluated their chemical and functional properties and used the extracts to prepare seasoned rice noodles. The four insect species contained 67–69% moisture, 13–18% protein, 6–10% fat, and 4–5% ash. The insect protein concentrate (IPC) contained 73–77% protein, and had high water solubility and emulsion stability (80–88%), moderate emulsion ability (56–65%), but low water- and oil-holding capacity (19% and 8–9%, respectively). The distinctive amino acid components in the IPC were glutamic acid and aspartic acid. In order to improve the nutritional and textural qualities of seasoned rice noodles, the IPC was added at rates of 0, 2, 4, 6, 8, and 10% by weight of rice flour. The results showed that the cooking weight was not significantly different from plain rice noodles; however, the 8% IPC fortified rice noodles had the highest tensile strength, whereas the lightness, yellowness, and redness decreased with an increase in insect protein content. This study demonstrates success in using 2–8% of IPC in rice noodles as a stabilizing or thickening agent.