Physicochemical Properties, Fractionation and Fatty Acid Composition of Oil Extracted from Black Soldier Fly (Hermetia illucens) Larvae

Abstract

Globally, population growth is increasing gradually, leading to a rising demand for edible oil; however, resources are limited. There is a need to find alternative sources to fulfill this demand rather than relying solely on traditional ones. In this work, black soldier fly larvae (BSFL) were used as a source of edible oil. Oil was extracted using both the Soxhlet extraction method and the direct solvent extraction method. The physicochemical properties of the oils extracted by these methods were determined. For Soxhlet and direct solvent extraction, respectively, the values were as follows: specific gravity (0.9087±0.0001 and 0.9141± 0.0028), refractive index (1.4527±0.0153 and 1.4601±0.0107), saponification value (239.52± 6.38 and 243.42 ± 4.52 mg KOH/g), iodine value (50.37±1.53 and 52.00±2.16 g I₂/100g oil), peroxide value (2.01±0.28 and 2.02±0.11 mEq O₂/kg), and acid value (0.4527±0.0183 and 0.4608±0.0132 mg KOH/g). The total saturated, monounsaturated, and polyunsaturated fatty acids for oils extracted through Soxhlet and direct solvent methods were 59.3% and 52.5%, 24% and 28.2%, and 16.7% and 19.3%, respectively. TLC profiles of the extracted oils showed cholesterol esters, high amounts of triacylglycerols, free fatty acids, cholesterol, and traces of 1,2- and 2,3-diacylglycerols. The total steroid and α-tocopherol contents for oils extracted by Soxhlet and direct solvent methods were 16.26±2.21 and 17.69±1.81 mg/100g oil, and 12.28±0.59 and 14.02±1.15 mg/100g oil, respectively.