Lipid profile and growth of black soldier flies (Hermetia illucens, Stratiomyidae) reared on by‐products from different food chains

Abstract

BACKGROUND The total amount of bio‐waste produced annually in the EU by the food and beverage chains is estimated at 37 billion kg. The use of insects for the valorization of by‐products from these value chains may represent a sustainable solution. This study aimed to investigate the by‐products obtained from different food chains and used for the rearing of black soldier fly (BSF) prepupae, and to evaluate the content and profile of the lipid extracted from the prepupae and outline its possible applications. The substrates used in this experiment were: (i) industrial by‐products (brewery spent grains, cows’ milk whey, grape stalks, and tomato peels and seeds) and (ii) by‐products from retailers (bread dough, fish scraps, and spent coffee ground). Fat extracted from prepupae using an adjusted Folch method was used for total lipid content and fatty acid profile. RESULTS The best larval performances were obtained from beer (0.22 gweight per prepupa), tomato (0.19 gweight per prepupa), and cheese (0.14 gweight per prepupa) food‐chain by‐products. The extremely different compositions of the substrates were reflected in the differentiated lipid profile of the BSF prepupae and in the range of ratios between unsaturated and saturated fatty acids, which varied from 0.37 for cows’ milk whey to 1.34 for tomato peels and seeds. CONCLUSION The lipids, proteins, and chitin extracted from prepupae are high‐value bio‐based products that could be used in the feed / food industry or for the development of innovative biomaterials, such as biodiesel. These results suggest that food‐chain by‐products are the best candidates for insect‐bioconversion purposes. © 2020 Society of Chemical Industry

Antimicrobial Biomasses from Lactic Acid Fermentation of Black Soldier Fly Prepupae and Related By-Products

“…This study focused on Hermetia illucens, also called black soldier flies (BSF), a Diptera belonging to Stratyiomidae family. In accordance with Commission Regulation (EU) 2017/893 [8], this insect is one of the seven species approved for feeding of aquaculture animals and thanks to its high nutritional value [9], and to its ability to convert industrial waste [10][11][12][13][14] is one of the most promising to be used in the feed industry.…”

Bioplastic Film from Black Soldier Fly Prepupae Proteins Used as Mulch: Preliminary Results

“…Insects like BSF already proved to be a useful tool for a circular economy in agro-food contexts by efficiently converting the biowaste into a biomass rich in proteins, lipids and chitin [43,44]. The residual frass after BSF larvae rearing can be used as a soil improver with compost-like properties [26,29] that is suitable for fertilizing horticultural crops and comparable with the traditional compost obtained by valorizing agro-industrial by-products [45,46].…”

Insights Into the Immune Response of the Black Soldier Fly Larvae to Bacteria

“…To exclude potential side effects of the puncture or the buffer used to resuspend the bacteria, larvae punctured with a sterile needle only or injected with sterile PBS (5 µl) were analyzed at different time points (negative controls) (Figure S1). Additional controls were performed by examining starved naïve larvae at different time points (3,6,14,24, and 48 hours) to exclude possible effects of food deprivation on different immune markers (Figure S2).…”

“…In recent years, the possibility of rearing saprophagous insects on organic residues has been attracting increasing interest as insectmediated bioconversion not only represents a strategy to valorize waste, but also to obtain bioproducts, thus generating circular economy value chains (1). In this scenario, the larvae of the black soldier fly (BSF), Hermetia illucens (Diptera: Stratiomyidae), play a key role since they have an outstanding ability to grow on a variety of by-products of different supply chains (2)(3)(4) and larval proteins can be used not only for formulating feedstuff for poultry, pigs, and fish (5), but also for manufacturing bioplastics (6). Moreover, BSF larvae represent a valuable source of lipids for producing biodiesel (7), chitin (8), and antimicrobial peptides (9).…”