Bioconversion of Lathyrus clymenum (Fava Santorinis) Legume Pericarps into Nutritious Insect Meal via Black Soldier Fly (Hermetia illucens) Larval Rearing

The increasing global demand for sustainable production of high-nutritional-value food and feed has emerged the need of harnessing the agro-industrial residues applying various innovative bioconversion strategies. In this context, the utilization of legume production wastes constitutes an intriguing subject because of their high content in nutritious molecules. The study herein concerns the incorporation of Fava Santorinis (Lathyrus clymenum) pericarps, an agro-industrial byproduct, into Black Soldier Fly (BSF, Hermetia illucens) larvae rearing diets to produce nutritious insect meals. Thus, four dietary treatments of BSF larvae were evaluated consisting of a commercial feed as control diet and three experimental diets incorporating 15%, 30% and 45% inclusion levels of fava bean pericarps. When BSF larvae reached their sixth instar stage, their growth performance and the nutritional content of the produced insect meal were assessed. Best results were obtained for BSF rearing with feed containing 30% and 45% pericarps, establishing the valorization of a large amount of pericarp, achieving a high growth rate and a rich protein content exceeding 30%. On the other hand, the presence of saponines was not determined, although the overall larvae performance indicates a high tolerance to their presence. Finally, the assessment of insect meals lipidic profiles revealed the prevalence of saturated lauric acid, an established potent antimicrobial agent, along with lower amounts of unsaturated Ω-6 linolenic acid and Ω-3 linoleic acid acids. The results herein demonstrate a sustainable strategy for the bioconversion of Fava Santorinis production waste to nutritious animal feed in the context of circular economy.