Omega-3 fatty acids and bioactives in aqueous-extracted oils from seven edible insects

Globally, there is urgent search and research interest towards alternative sources of polyunsaturated omega-3 fatty acids (ω-3 FA) due to sustainability challenges faced by dependence on fish and plant-derived sources. Limited information exists on insects despite their promising potential. This work analyzed oils from seven insect species commonly consumed globally compared to commercial sesame oil using coupled gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS). Oil yields from insects ranged between 11.1 mg/g to 115.3 mg/g. Over 67 fatty acids, α-tocopherol [vitamin E] and eight flavonoids were identified. All insect oils contained ω-3 FA [i.e., α-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA)]. The fifth instar of desert locust [Schistocerca gregaria] had the highest levels of ALA (9.4 µg/mg), EPA (1.0 µg/mg), and DHA (3.1 µg/mg) compared to sesame oil with ALA (7.9 µg/mg) only. Polyunsaturated fatty acids were dominant in sesame oil. Over 50% of monounsaturated fatty acids were present in S. gregaria, Spodoptera frugiperda and Bactrocera dorsalis. Gryllus bimaculatus oil contained mostly saturated fatty acids (51.1%). The levels of α-Tocopherol [vitamin E] were significantly higher in all the insect oils except S. frugiperda. Flavonoids such as quercetin and luteolin were abundantly present in S. gregaria and G. bimaculatus oils. These insects are widely consumed across the globe and can be farmed using fewer resources. Thus, widening the research scope would offer new opportunities to advance use of edible insects to address interconnected nutritional and health challenges.