Aqueous ethyl acetate as a novel solvent for the degreasing of black soldier fly (Hermetia illucens L.) larvae: degreasing rate, nutritional value evaluation of the degreased meal, and thermal properties

Novel Insights on the Sustainable Wet Mode Fractionation of Black Soldier Fly Larvae (Hermetia illucens) into Lipids, Proteins and Chitin

The black soldier fly larvae (BSFL) is a sustainable ingredient for feed applications, biofuels, composite materials and other biobased products. Processing BSFL to obtain lipid and protein fractions with enhanced functional properties as a suitable replacement for conventional feed ingredients has gained considerable momentum. In this regard, a novel and sustainable wet mode fractionation (WMF) scheme for BSFL was explored. Fresh BSFL were steam blanched and pulped to obtain BSFL juice and juice press cake. Subsequent treatment of BSFL juice employing homogenization or enzyme incubation and further centrifugation resulted in the obtention of four different BSFL fractions (Lipid—LF; Cream—CF; Aqueous—AF; and Solid—SF). Total energy consumption for a batch BSFL (500 g) WMF process was 0.321 kWh. Aqueous and solid fractions were the predominant constituents of BSFL juice. Lauric acid (44.52–49.49%) and linoleic acid (19.12–20.12%) were the primary fatty acids present in BSFL lipids. Lipid hydrolysis was observed in lipids belonging to the solid (free fatty acids > triacylglycerides) and cream fractions. Aqueous fraction proteins (ctrl) displayed superior emulsion stability and foam capacity than other treatments. Juice press cake retained 60% of the total chitin content and the rest, 40%, was found in the solid fraction (ctrl). The material distribution of principal constituents in different fractions of the WMF process and amino acid profile was elucidated. Overall, the versatile WMF process proposed in this study involves simple unit operations to obtain functional ingredients from BSFL, which can be further explored by researchers and industry stakeholders.

Black Soldier Fly (Hermetia illucens) Larvae Meal Modulates Intestinal Morphology and Microbiota in Xuefeng Black-Bone Chickens

The addition of Hermetia illucens larvae meal (HILM) to the feed could contribute to particular antimicrobial and intestinal health in animal husbandry. This study was conducted to investigate the effects of HILM on intestinal morphology and microbial diversity in different intestinal segments of Xuefeng black-bone chickens. All of 432 birds (45 weeks old) were randomly assigned to four equal groups with six replicates and 18 hens in each replicate: (A) basal diet, (B) basal diet with 1% HILM, (C) basal diet with 3% HILM, and (D) basal diet with 5% HILM. The results showed that, compared with the basal diet group, the HILM supplement significantly increased the abundance-based coverage estimator (ACE) and Chao index in cecum (p < 0.05). Diet with 1% HILM significantly increased the villus height (VH) of the duodenum (p < 0.05) and cecum microbial diversity as represented by the Simpson index (p < 0.05). In particular, 1% HILM displayed a markedly increase in the genus unclassified Bacteroidales (cecum, p < 0.05). A basal diet with 3% HILM markedly increased the beneficial genus Romboutsia (jejunum, p < 0.05). Also, principal component analysis (PCA) cluster analysis showed that 3% of HILM was more individual than other groups (p < 0.05). However, 5% HILM decreased the VH and the ratio of villus height to crypt depth (VH/CD) of the jejunum and increased beneficial bacteria such as Staphylococcus (p < 0.05), which was regarded as pathogenetic genera. In conclusion, we found that HILM improved intestinal morphology and increased microbiological diversity and species abundance. Together, dietary supplementation of 1 or 3% HILM might benefit the intestinal morphology and intestinal microbiota of Xuefeng black-bone chicken. However, the addition of 5% HILM could decrease VH and the ratio of VH/CD of the jejunum and increased pathogenetic genera. HILM was an excellent protein substitute for Xuefeng black-bone chickens, which could meet the nutritional requirements under the condition of less feed. These results provide information for HILM meal as an alternative source of soybean meal in Xuefeng black-bone chickens’ feed.

Physico-chemical and colloidal properties of protein extracted from black soldier fly (Hermetia illucens) larvae

The black soldier fly larvae (BSFL), Hermetia illucens (Linnaeus), has been largely utilized for animal feed. Due to its interesting composition, BSFL has great potential to be further implemented in the human diet. Herein we compared the flour and protein extract composition based on their moisture, ash, amino acids, mineral, and protein content. To have wide knowledge on protein profile and behavior, SDS-page electrophoresis, Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) were used to give information about protein structure and thermal stability, respectively. The flour and protein extract contained respectively 37.3% and 61.1% of protein. DSC graph reported a glass transition temperature around 30 °C, recognizable by a shift in the curve, and an endothermic peak for solid melting at around 200 °C. FTIR analysis showed the main amide bands (A, B, I, II, III) for the flour and protein extract. The foam properties of BSFL protein extract were explored under different temperatures treatment, and the best foam stability was reached at 85 °C with 15 min of treatment. The data highlight the promising techno-functional properties of BSFL protein extract, and that the nutritional composition might be suitable for further use of BSFL as food fortification system.

Black Soldier Fly Full-Fat Larvae Meal is More Profitable than Fish Meal and Fish Oil in Siberian Sturgeon Farming: The Effects on Aquaculture Sustainability, Economy and Fish GIT Development

Simple Summary

The practical use of alternative feed materials must be both sustainable and profitable. Therefore, the aim of this study was to assess the impact of black soldier fly full-fat larvae meal (BSFL) on environmental and economic aspects as well as gastrointestinal tract (GIT) development in Siberian sturgeon nutrition. The experimentally obtained data were used for calculations of fish meal (FM) and fish oil (FO) relative usage per kg of fish gain. The economic conversion ratio and profitability per unit of fish gain were assessed also. The samples of intestinal and liver tissues were analysed in terms of villi height, width, and surface, and liver health. The study showed a high potential of BSFL usage up to its highest used incorporation that was 30% of the diet. The environmental sustainability of the diets was increased not only by the reduction in FM and FO use but also by the increase in feed conversion efficiency. Thus, even though the price of BSFL was higher than FM and FO, the profitability of fish production was improved, finding its optimum at the levels of 10% and 15% BSFL incorporation. Moreover, health beneficial effects of BSFL were observed in alterations of GIT development.

Abstract

This study provides data on the environmental sustainability, economic profitability, and gastrointestinal tract development of Siberian sturgeon diets containing black soldier fly full-fat larvae meal (BSFL) for a fish meal (FM) and fish oil (FO) replacement. BSFL was used at 5%, 10%, 15%, 20%, 25%, and 30% of the diet, replacing by up to 61.3% of FM and 95.4% of FO. BSFL positively affected the feed efficiency ratio, and lowered FM and FO usage per kg of fish gain. All the BSFL diets showed a sustainable fish-in fish-out (FIFO) ratio, which was lowered by up to 75% in comparison to the control. Economic assessment per kg of fish gain showed that the most lucrative variants were variants with 10% and 15% BSFL, it finds a mode of action in improvements of the gastrointestinal tract development, including increased pyloric caeca and proximal intestine shares and enhanced villus height and area. Thus, in Siberian sturgeon, BSFL may be used not only as an FM and FO replacer but also as a functional material due to its feed utilization and beneficial health effects, which are reflected in its high sustainability and favourable economics.

Larvae Mediated Valorization of Industrial, Agriculture and Food Wastes: Biorefinery Concept through Bioconversion, Processes, Procedures, and Products

Each year, the food supply chain produces more than 1.3 billion tons of food and agricultural waste, which poses serious environmental problems. The loss of the massive quantity of secondary and primary metabolites retrievable from this resource is a significant concern. What if there is a global solution that caters to the numerous problems arising due to the humongous volume of waste biomass generated in every part of the world? Insects, the tiny creatures that thrive in decaying organic matter, which can concentrate the nutrients present in dilute quantities in a variety of by-products, are an economically viable option. The bioconversion and nutritional upcycling of waste biomass with insects yield high-value products such as protein, lipids, chitin and frass. Insect-derived proteins can replace conventional protein sources in feed formulations. Notably, the ability of the black soldier fly (BSF) or Hermetia illucens to grow on diverse substrates such as agri-food industry side streams and other organic waste proves advantageous. However, the data on industrial-scale extraction, fractionation techniques and biorefinery schemes for screening the nutritional potential of BSF are scarce. This review attempts to break down every facet of insect processing and analyze the processing methods of BSF, and the functional properties of nutrients obtained thereof.