Effects of High Pressure and Ultrasonication Pretreatments and Supercritical Carbon Dioxide Extraction on Physico-Chemical Properties of Edible Insect Oils

Abstract

Edible insects have gained increased attention as the important and sustainable source of nutrients for both human and animal consumption due to their rich content of protein, oil, fiber (as chitin), vitamins, and minerals. This study focuses on examining the effects of advanced pretreatments and oil extraction methods from prominent edible insect species commercially cultivated in Thailand, namely the house cricket (Acheta domesticus), black soldier fly larvae (Hermetia illucens), and silkworm (Bombxy mori). The raw insect samples underwent pretreatment using high pressure processing (HPP) at 200–600 MPa for 5 min or ultrasonication (UL) at 37 kHz for 5–15 min, followed by dehydration and extraction using supercritical carbon dioxide (SC-CO₂) or solvent extraction. The study revealed that HPP significantly reduced the initial microbial load of all edible insects by 6–8 log cycles, while UL showed a slight effect on microbial reduction. Additionally, pretreatments notably improved the oil extraction yield of most samples by disrupting the integrity of the cell membrane, facilitating the release of oils. The extracted edible insect oils were rich in unsaturated fatty acids, omega 3, 6, and 9, making them suitable for various applications such as cosmetics, food, and feed additives. Furthermore, the protein meals obtained as a residue after oil removal were identified as potential meat alternatives or replacements in food or feed formulations. This study provides valuable insights into the potential of edible insects as a sustainable source of oil and protein, highlighting the significance of pretreatments and extraction methods in maximizing their utility for various applications in the food, cosmetic, and feed industries.