Removal of fat from crushed black soldier fly larvae by carbon dioxide supercritical extraction

Abstract

The larvae of the black soldier fly, Hermetia illucens, contain high amounts of protein and fat, and so are a good feed source. However, this high fat content hinders the production of such feed. The excess fat must thus be removed to enable the larvae to be used as a feedstock e.g., for aquaculture and livestock. Firstly, the use of hot water treatment as a strategy for extracting fat from dried larvae was tested. It was found that this process reduced the fat content of the raw material (from 30 to about 16%). However, the resulting product was still not suitable for feed processing. Next, the use of a carbon dioxide supercritical extraction system on crushed larvae was studied. This system time-dependently reduced the fat content to less than 6.6% and less than 4.6% after treatments for 2 and 6 h, respectively, with a pressure of 350 bar used on larval particles of 10-18 mesh in size. Therefore, subjecting 10-18 mesh crushed larval powder to carbon dioxide supercritical extraction at 350 bar for 6 h yielded a larval powder with a fat content of 5% or less. Based on this finding, this method is proposed to be a suitable alternative for further processing of larvae feedstock.

Insect Fat in Animal Nutrition – A Review

“…Kierończyk et al (2020) used SC-CO2 to extract the fat from H. illucens with 300 bar and a temperature of 40°C. Furthermore, Kim et al, 2019, showed that the SC-CO2 extraction method could be an effective method for the defatting of H. illucens (HI) meals subjected to 10-18 mesh crushing at 350 bar for 6 h. A 95% fat extraction yield was achieved.…”

Comparison of Sustainable Lipid and Protein Removal Methods for the Isolation of Insect Chitin from Black Soldier Fly Exoskeleton

“…However, further optimization of the supercritical carbon dioxide process, especially with the use of a co-solvent, might improve the extraction yield in future work . The choice of lipid extraction method impacts protein extraction, and successful defatting and protein precipitation are important for obtaining good yields and purifications of extracted insect chitin …”

Use of Black Soldier Fly Larvae for Food Waste Treatment and Energy Production in Asian Countries: A Review

“…Furthermore, the defatting process required when using BSFL as feed was tested in Korea using hot water and supercritical CO 2 extraction [46]. When BSFL defatting was performed using hot water, the fat content in BSFL was reduced to 16%.…”

“…In contrast, when the supercritical CO 2 extraction method was used, the fat content in BSFL was reduced to 5% or less. Therefore, it was concluded that the supercritical CO 2 extraction method may be a suitable method for the defatting of BSFL for its use as feed [46].…”

“…Although the body composition of BSFL significantly differs depending on the substrate (Table 3), the high protein content of BSFL make them a good nutrition source of animal feed [46,69]. In fact, the crude protein content of BSFL after defatting was 60% [69].…”