The global vegetable oil production is located in only a few countries. This is a considerable concern for global food security as any destabilization of the global trade, or any obstacle to the production or export of these commodities, will lead to product shortage and soaring prices. In contrast, black soldier fly larvae can be farmed almost everywhere in the world, which is a strong asset for this oil to become a major ingredient for animal nutrition.
Black soldier fly farming is less than ten years old, but it has the potential to produce huge volumes of alternative insect-based products in the coming decades. Because insect oil is a major product of insect farming, it is critical to review its potential to support a healthy diet for animals.
The primary markets for insect products are the aquaculture, livestock and pet industries. Black soldier fly oil being a novel ingredient, two questions are frequently raised: what are the benefits compared to plant-based oil, and how does it contribute to animal nutrition and health?
GLOBAL VEGETABLE OIL PRODUCTION STATISTICS
During 2021-2022, the five most consumed vegetable oils in the world were, palm oil (71.2 million tons/year), soybean oil (59.3 million tons/year), rapeseed oil (29.4 million tons/year), sunflower oil (17.9 million tons/year) and palm kernel oil (8.3 million tons/year), respectively. Collectively, these five vegetable oils represented 91.1% of the world oil consumption (Statista, 2023).
Prices for these five oils have been extremely volatile over the last three years, increasing March 2020 (due to Covid-19 crisis) until reaching a peak in March 2022 (due to the war between Ukraine and Russia). From March to December 2022, the oil prices decreased, but without coming back to the initial values of March 2020 (Figure 1).
The majority of palm oil and palm kernel oil production is geographically circumscribed to Indonesia, Malaysia and Thailand, accounting for almost 90% of the global production. Similarly, 80% of the soybean production comes from Brazil, the United States of America and Argentina together. Regarding global sunflower production, Ukraine and Russia were the first and second highest producers in 2021 respectively, representing about 60% (US Department of Agriculture, 2023).
The global vegetable oil production is thus located in only a few countries. This is a considerable concern for global food security as any destabilization of the global trade, or any obstacle to the production or export of these commodities, will lead to product shortage and soaring prices. In contrast, black soldier fly larvae can be farmed almost everywhere in the world, which is a strong asset for this oil to become a major ingredient for animal nutrition.
FATTY ACID PROFILES OF BLACK SOLDIER FLY OIL AND VEGETABLE OILS
Black soldier fly oil is mainly composed of six fatty acids that represent around 90% of the profile: lauric, palmitic, oleic and linoleic acids, and to a lesser extent, myristic and stearic acids. Lauric acid is the most abundant, representing around 1/3 (Table 1). The large-scale oil production data used in Table 1 below are stemming from Veolia Bioconversion Malaysia, a black soldier fly farm in Bestari Jaya (Malaysia), whose products are commercialized under the brand Entofood by Veolia and under the name Entolipid for the insect oil, and Entomeal™ for the insect meal.
It is important to keep in mind that black soldier fly fatty acid profile depends on the substrate that is fed to the larvae, as observed in Table 1. Black soldier fly oil can be enriched in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) when the larvae feed on substrates such as fish or shellfish (Ewald et al., 2020). This is particularly interesting as these two fatty acids are usually not found (or present in only trace amounts) within black soldier fly oil. Feeding black soldier fly larvae with fish and shellfish is for now prohibited by the European Union regulation, but if the legislation changes, it may open new avenues for the insect industry to produce larvae with a bespoke enriched fatty acid profile.
The proportions of these six fatty acids within the five most consumed vegetable oils is reported in Table 2. Although coconut oil is only the 8th most consumed vegetable oil in the world (2021-2022: 3.5 million tons/year; Statista, 2023), the fatty acid profile is also featured in Table 2 due to the similarity with black soldier fly oil. The fatty acid profiles of palm, soybean, rapeseed, and sunflower oils are quite different to black soldier fly oil, for example, they contain little to no lauric acid. In contrast, the fatty acid profile of black soldier fly oil is closer to palm kernel and coconut oils because they are rich in lauric acid (around 1/2 of the profile of these two oils). However, black soldier fly oil is still partly different from these two oils, for instance, it is much richer in linoleic acid.
To summarize, although black soldier fly oil is rich in lauric acid similarly to palm kernel and coconut oils, it should not be compared to any vegetable oil, and rather should be considered as a new sustainable ingredient for animal nutrition.
THE USE OF BLACK SOLDIER FLY OIL IN ANIMAL NUTRITION
The fatty acid profile of black soldier fly oil is interesting, from a nutritional point of view, for a wide range of animals. In poultry, the only essential fatty acid that cannot be synthesized, and so must be obtained from the diet, is linoleic acid (Baião and Lara, 2005), which is found in black soldier fly oil (linoleic acid represents around 22% of the fatty acid profile in Entolipid). In freshwater fish and swine, the essential fatty acids are linoleic and alpha-linolenic acids (Guillaume et al., 1999; Liu, 2015). Black soldier fly oil can be used as a complement to another oil source rich in alpha-linolenic acid, such as soybean, rapeseed, or even flaxseed oil. Regarding marine fish, arachidonic fatty acid, EPA and DHA are also essential (Guillaume et al., 1999). Black soldier fly oil, enriched with EPA and DHA if needed, could be used as a partial substitute to fish oil, representing thus a much more sustainable alternative. The same considerations apply to formulate pet food, as the essential fatty acids for marine fish, dogs and cats are the same (National Research Council, 2016). The key asset of black soldier fly oil is to be a sustainable source of lauric acid: it does not simply provide a balanced diet, but it is also highly beneficial for animal health.
FUNCTIONALITIES OF BLACK SOLDIER FLY OIL AND THEIR IMPACT ON ANIMAL HEALTH
Beyond the fact that black soldier fly oil is able to fulfill the metabolic requirements of various animals, it also promotes animal health. Lauric acid has a demonstrated antimicrobial effect (Yoon et al., 2018). In particular, lauric acid destabilizes bacterial cell membranes (becoming permeable) and inhibits their exchanges and energy metabolism (Borrelli et al., 2021), which ultimately leads to bacteria death. For example, lauric acid is effective against Staphylococcus species, Streptococcus species, Helicobacter pylori, Clostridium perfringens or Propionibacterium acnes (Yoon et al., 2018).
Beneficial effects of black soldier fly oil on gut microbiome, and thus animal health, have already been demonstrated in rabbits (Dabbou et al., 2020), piglets (Spranghers et al., 2018), turkey (Sypniewski et al., 2020) and Siberian sturgeon (Acipenser baerii; Józefiak et al., 2019). In the case of turkey, black soldier fly oil did not only inhibit the development of pathogenic bacteria, but it also reduced gastrointestinal tract inflammation (Sypniewski et al., 2020). In Siberian sturgeon, Rawski et al. (2021) demonstrated that black soldier fly oil had beneficial effects on the development of the gastrointestinal tract, particularly a larger pyloric caeca and surface of the intestinal villi. In broiler chickens, Chen et al. (2022) reported that the inclusion of black soldier fly oil within the diet increased the blood plasma levels of immunoglobulins (antibodies) and interleukins (regulating immune response), suggesting the animals’ immune system was strengthened. In 2022, Veolia conducted a trial (Verstraete et al., 2023) on juvenile whiteleg shrimp (Litopenaeus vannamei) fed with 2% inclusion of Entolipid plus 2% inclusion of Entomeal™, at Kasetsart University (Thailand). After 45 days of feeding, the shrimps fed with black soldier fly ingredients were 26% heavier than the ones fed without. Then the shrimps underwent a pathogenic challenge using Vibrio parahaemolyticus (leading to acute hepatopancreatic necrosis disease). Seven days after the challenge, the group fed with black soldier fly ingredients exhibited a better survival rate (64%) than the one fed without (only 50%). At histological level, significant signs of sloughing were observed in hepatopancreatic tubule epithelial cells in the group fed without black soldier fly ingredients, whereas they mostly survived in the group fed with black soldier fly ingredients (Figure 2). These results were linked to laboratory analyses revealing an increase in the phagocytosis activity, in the activity of enzymes involved in the immune response, and a decrease of V. parahaemolyticus abundance.
Black soldier fly oil is particularly rich in lauric acid (around 1/3 of its fatty acid profile). It is also abundant in palmitic, oleic and linoleic acids. Although lauric acid is prevalent in palm kernel and coconut oils, black soldier fly oil is a novel ingredient opening new opportunities for animal nutrition. Indeed, black soldier fly is suitable for poultry, pig and fish (freshwater or marine) nutrition, as well as for pet food. Beyond the nutritional quality, recent trials suggest that black soldier fly oil can support animal health. In particular, it can inhibit pathogenic bacteria development but also support the immune system in several species (e.g. whiteleg shrimp).
Black soldier fly oil is thus an exciting ingredient to add in any premix of oils traditionally applied in livestock or pet diet. Whether black soldier fly oil could also be beneficial in human nutrition is still an open question that deserves investigation. However, black soldier fly ingredients have not been allowed for human consumption by the European Union regulation yet. Black soldier fly oil might also be used for purposes out of the scope of nutrition, for instance to produce rinse-off cosmetics with antimicrobial properties, such as foaming soaps or shower gels. Ultimately, black soldier fly oil has a bright future ahead.
About Charles Rodde, PhD
After working 4 years as a researcher in the aquaculture sector, with a strong focus on how to substitute fish meal and oil in farmed fish diet, Charles Rodde got convinced that insect farming was the most powerful solution to make aquaculture and more generally world food production more sustainable. He then decided to join the insect industry at Entofood (Malaysia), as a R&D manager. His work mainly focuses on black soldier fly nutrition and zootechny at larval stage. He develops and implements research projects but also provides technical support to Veolia production sites.