Copping out of novel feeds: HOW climate change pledgers and food summits overlooked insect protein.

The intention with this critical review is to appraise recent work done on insect proteins as animal feeds, and to discuss the possible factors which led to the ruling out of insect proteins by food and feed commissioners, as well as climate change pledgers. Of late, edible insect larvae have gained popularity as a promising protein source. On the basis of proximate analysis, insect species such as Tenebrio molitor, Musca domestica, Acheta domestica, Zophobas morio and Hermetia illucens have been reported to contain substantial amounts of protein, essential amino acids and minerals. Given these chemical properties, insects may be fruitfully utilized as a partial or sole protein source for monogastric rations. Although insect larvae hold immense potential as promising sustainable protein ingredients which are both ecologically and environmentally friendly, these unconventional feedstuffs are frequently overlooked and/or excluded from policies and legislation on feedstuff of animal origin, at local and international summits which pledge to develop sustainable food systems. Concerns about food insecurity, our expanding carbon footprint and deteriorating ecosystems, dictate that food and climate change summits bring to the mitigation table the concept of transitioning animal diets. A change must be effected from standard to sustainable diets, starting with a declaration on environmental impact and climate change concerns related to soybean cultivation and marine loss due to overfishing. The available literature on the chemical properties and environmental impact of fishmeal and soyabean meal production was scrutinized by accessing electronic databases and comparing these to insects' nutritional composition and the impact which insect rearing has on the environment. As the literature search results revealed, information on the specific laws dealing with insect proteins as feed ingredients is scant, while the existing laws vary greatly. This has implications for innovation, as well as the trade in insect protein at a global level.

Unravelling the nutritional and health benefits of wheat bread enriched with meat powder from laying hen fed diet with insect (Hermetia illucens) meal.

Wheat bread is among stable foods that are nutritionally imbalanced, thus enrichment is crucial. We evaluated the nutritional impact of high-valued wheat bread enriched with varying levels of meat powder from hen fed diet with insect (Hermetia illucens)-based meal. Crude protein and ash in bread increased with increasing inclusion of meat powder. Limiting amino acids like lysine and threonine in enriched bread products increased by 3.0-4.5 and 1.8-3.1-folds, respectively. Omega 3 fatty acids were significantly enhanced in bread fortified with meat powder. Vitamins (retinol, nicotinic acid, and pantothenic acid) were significantly increased in supplemented bread products. Iron, zinc, and calcium increased by 1.1, 1.2 and 3.0-folds in enriched bread with 30% meat powder. Colour, flavour and overall acceptability of breads prepared with 25 and 30% meat powder were highly ranked. Our findings demonstrate that meat powder (i.e., from hen fed insect-based diets) enrichment would provide added health and nutritional benefits to bread products without having adverse effects on any functional or sensory properties. Thus, this could be a novel strategy and trend for improving bread products, that might generate increasing demand for a healthier consumer-oriented lifestyle.

Low inclusion levels of Tenebrio molitor larvae meal in laying Japanese quail (Coturnix japonica, Gould, 1837) diet improve the intestinal morphometry, enzymatic activity and caecal short chain fatty acids profile.

One hundred twenty, 12 weeks old laying Japanese quails (JQ) were equally divided into 4 groups (6 replicates of 5 birds/group). The control group (CON) fed a corn-soybean diet; TML1.4, TML2.8, and TML5.6 groups fed a diet where a Tenebrio molitor larvae meal (TML) was included at 1.4, 2.8, and 5.6%, respectively. The trial lasted 54 days. The villi height (VH) and the crypt depth (CD) linearly decreased from the control to the TML5.6 group (P < 0.01) in the duodenum, while an opposite trend was observed for the Ab+ mucous cells count (P < 0.01). The highest VH/CD ratio was found in the TML1.4 group (P < 0.01). In the jejunum a lower VH was observed in the TML1.4 compared to the CON group; the Ab+ mucous cells increased (P < 0.01) according to the increase of the TM inclusion in the diet, while the highest VH/CD ratio (P < 0.01) was recorded in the TML2.8 group. In the duodenum only the L-ANP has been affected by TML (P < 0.001), with a quadratic and linear effect. The L-ANP is affected by the dietary treatment in the jejunum (P < 0.05), where showed a quadratic effect with the highest value in TML2.8. The % of butyric acid is maximized (P < 0.05) with the TML1.4 diet and that of the isobutyrate and valeric acids increased (P < 0.01) from TML1.4 to TML5.6. The use of TML at 1.4% in laying quail diets can be considered as a way to improve the intestinal health of the birds.

Black Soldier Fly Larvae Meal in the Diet of Gilthead Sea Bream: Effect on Chemical and Microbiological Quality of Filets.

The chemical and microbiological characteristics of filets of Spaurus aurata L. specimens fed with diets containing a Hermetia illucens meal (HIM) at the 25, 35, and 50%, as a partial replacement for fish meal (FM) were evaluated. The diets, formulated to satisfy the nutritional needs of fish, were isoenergetic (22 MJ/kg gross energy), isonitrogenous (43 g/100 g, a.f.), and isolipidic (19 g/100 g, a.f.). Seventy-two specimens were randomly killed after 186 days of growing trials. Then, the filets were analyzed for chemical profile, fatty acids, amino acids, minerals, and microbial flora. Data were subjected to statistical analysis. No significant differences were observed in chemical composition. The sum of polyunsaturated fatty acids (PUFAs) showed a similar content in the filets; eicosapentaenoic acid was similar in the filets of HIM0, HIM35%, and HIM50%, whereas docosahexaenoic acid was higher in filets of the HIM0 group. n3/n6 PUFA ratio and the sum of EPA + DHA showed a high value (p < 0.001) in filets of the group fed with FM. No significant difference was observed in thrombogenic index and hypocholesterolaemic/hypercholesterolaemic ratio in the groups; the atherogenic index showed a higher value (p = 0.001) in the HIM50% group. Indispensable amino acids showed some significant (p < 0.0001) differences in the groups; arginine and phenylalanine content was higher in the filets of fish fed with FM; isoleucine and valine content was higher in the filets of HIM50%; leucine, lysine and methionine content was lower in the filets of HIM35%; histidine content was lower in the filets of HIM25%; tryptophan content was lower in filets of the HIM50% group. EAA/NEAA ratio showed highest value in the filets of the group that received FM. The presence of HIM in the three diets kept chromium, manganese, iron, copper, zinc, and nickel levels lower than those recommended by various authorities. Ca/P ratio showed a higher level (p < 0.0001) in the group fed with FM than those fed with diets containing HIM. The insect meal in the diets did not influence the microbiological profile of fish. Use of HIM as an unconventional feed ingredient in Sparus aurata diet looks promising, although the quality of filets may be affected.

Supplementation of Sulfur-Containing Amino Acids or Essential Amino Acids Does Not Reverse the Hepatic Lipid-Lowering Effect of a Protein-Rich Insect Meal in Obese Zucker Rats.

The present study tested the hypothesis that the liver lipid-lowering effect of insect meal (IM) is caused by its low methionine concentration. A total of fifty, male obese Zucker rats were randomly assigned to five groups of 10 rats each (casein (C), IM, IM + Met, IM + Cys, and IM + EAA). While group C received a diet with casein, the IM-fed groups received a diet with IM as the protein source. In groups IM + Met, IM + Cys and IM + EAA, the diets were additionally supplemented with methionine, cysteine and essential amino acids (EAA), respectively. Hepatic concentrations of triacylglycerols and cholesterol, and hepatic mRNA levels and activities of lipogenic and cholesterogenic enzymes were markedly lower in the IM-fed groups than in group C (p < 0.05). All of these parameters either did not differ across the IM-fed groups or were only slightly higher in groups IM + Met, IM + Cys and IM+EAA than in the group IM. In conclusion, the results indicate that a difference in the amino acid composition between IM and casein, a low concentration of methionine in IM and a reduced cysteine synthesis secondary to a decreased methionine availability resulting from feeding IM are not causative for the lipid-lowering effect of IM.

Cafeteria-Type Feeding of Chickens Indicates a Preference for Insect (Tenebrio molitor) Larvae Meal.

This study aimed to determine whether broiler chickens display a preference for Tenebrio molitor larvae (TM) meal by evaluating ingredient acceptability and birds' performance. Sixty 14-day-old male chickens were assigned into two treatment groups (5 birds/pen, n = 6) in a cafeteria-type study: the control (C) group, and the TM group. Each pen was equipped with one bell drinker and four through feeders allocated side by side; all feeders of the C group contained a complete standard diet whereas each feeder of the TM group contained one of the following ingredients: ground corn, extruded semi-whole soybean, vitamin-mineral supplement mixture, and TM meal. Feed intake was recorded daily and growth was monitored periodically up to day 32. Chickens which had access to individual feed components showed a delay to display preference for TM, but consumed, overall, up to 50% of the total intake as TM meal. Feed intake and growth performance were lower in all periods for TM group (p < 0.02), whereas feed conversion ratio was improved on days 22-28 and days 29-32 of age (p < 0.01). Data from bivariate and multidimensional analysis indicate that birds started to reach a balance of ingredient intake at 25 days of age, showing a high correlation between consumption of each ingredient and the day of the experiment. Chickens exhibited a preference for T. molitor meal, resulting in improved feed efficiency, which allows us to conclude that it can be a suitable feed alternative for poultry.

Black soldier fly as dietary protein source for broiler quails: meat proximate composition, fatty acid and amino acid profile, oxidative status and sensory traits.

In the perspective of improving the sustainability of meat production, insects have been rapidly emerging as innovative feed ingredient for some livestock species, including poultry. However, at present, there is still limited knowledge regarding the quality and sensory traits of the derived meat. Therefore, the present study tested the effect of a partial substitution of soya bean meal and oil with defatted black soldier fly (Hermetia illucens) larvae meal (H) in the diet for growing broiler quails (Coturnix coturnix japonica) on meat proximate composition, cholesterol, amino acid and mineral contents, fatty acid profile, oxidative status and sensory characteristics. To this purpose, three dietary treatments were designed: a control diet (C) and two diets (H1 and H2) corresponding to 10% and 15% H inclusion levels, respectively, were fed to growing quails from 10 to 28 days of age. At 28 days of age, quails were slaughtered and breast meat was used for meat quality evaluations. Meat proximate composition, cholesterol content and oxidative status remained unaffected by H supplementation as well as its sensory characteristics and off-flavours perception. Differently, with increasing the dietary H inclusion, the total saturated fatty acid and total monounsaturated fatty acid proportions raised to the detriment of the polyunsaturated fatty acid fraction thus lowering the healthiness of the breast meat. The H2 diet increased the contents of aspartic acid, glutamic acid, alanine, serine, tyrosine and threonine thus further enhancing the biological value of the meat protein. As a direct result of the dietary content of Ca and P, the meat of quails fed with the highest H level, displayed the highest Ca and the lowest P values. Therefore, meat quality evaluations confirmed H to be a promising insect protein source for quails. The only potential drawback from feeding H to broiler quails regarded the fatty acid profile of the meat, therefore requiring further research efforts to understand to what extent the fatty acid profile of H can be improved.