*Perspective Chapter: Technological Strategies to Increase Insect Consumption – Transformation… DOI: http://dx.doi.org/10.5772/intechopen.108587*

analyzed, crickets have the highest protein content in the complete meal, followed by mealworm and BSFL. The insects with the least amount of fat content in the complete meal are mealworm followed by BSFL and then crickets. Complete meal has been widely used to formulate diets for productive animals, mainly in aquaculture [121–123], pet diets and snacks [48], and human food [44, 124]. Defatted meal has a significant increase in total protein content (20–23%) and a reduction in fat content [99]. Defatted meal has been used to develop new ingredients that concentrate insect protein (hydrolysates, isolates, protein concentrates) for humans [44], specialized pet foods, such as hypoallergenic foods [48], and bioactive extracts with potential nutraceutical use [125, 126].

The protein and fat content is variable for each insect, so **Table 1** presents ranges. The primary factors influencing fat content are intrinsic variability of each insect species, developmental stage (larvae, pupae or adults), the diets used to feed the insects during the rearing and fattening period, and environmental conditions [127, 128].

## **2.3 Transformation of insect meal and oil into new food/functional ingredients**

For mass consumption of insects to become the food of the future, it is necessary to transform insects into food ingredients of greater acceptability for the human population, using various technologies used by the food industry [129]. For animals, this is not necessary as insect meals and oil have high acceptability by aquaculture species [130], productive animals (pigs, hens, and chickens) [131–133], and domestic pets such as dogs and exotic animals [48]. **Table 2** and **Figure 2** present the new food and/or functional ingredients based on insect oil (**Figure 2A**) and meal (**Figure 1B**) commodities developed for humans. The main ingredients used as a base have been whole meal, defatted meal, and oil [172, 173]. More insect meal-based ingredients have been developed than insect oil. The developed oil-based ingredients are refined and deodorized oils, with better sensory properties (better odor and lighter yellow color). Emulsion technology has been applied to change the physical appearance of some insect oils, primarily BSFL, which as indicated above is solid at room temperature (**Figure 2A**), making it difficult to use in


#### **Table 1.**

*Protein and fat ranges in dry basis of whole and defatted meal, of common insects used in human and animal feed.*


*Perspective Chapter: Technological Strategies to Increase Insect Consumption – Transformation… DOI: http://dx.doi.org/10.5772/intechopen.108587*



*BSFL: black soldier fly larvae, HFL: house fly larvae, ML: mealworm larvae, ADL: Allomyrina dichotoma larvae, AD: Acheta domesticus, BM: Bombyx mori; SG: Schistocerca gregaria; AM: Apis mellifera; AL: Anastrepha ludens; ADI: Allomyrina dichotoma; PB: Protaetia brevitarsis; TE: Teleogryllus emma; OC: Oxya chinensis; MB: Melon bug; SB: Sorghum bug.*

#### **Table 2.**

*New food and/or functional ingredients developed from insect meal and oil.*

the formulation of diets, since it is complex to homogenize with the other ingredients and tends to form aggregates when combined with ingredients in powder form. After the emulsion process, liquid formulations are obtained (**Figure 2Ai**), with a milky appearance (**Figure 2Ai-iv**), which could be converted to powder by spray drying, to facilitate their use as a food ingredient and increase shelf life. These emulsions have been proposed as value-added ingredients for the food industry and as potential nutrient and drug vehicles for the pharmaceutical industry (in the case of nanoemulsions). Some nanoemulsions retain a milky appearance, while others tend to be transparent (**Figure 2Av**). BSFL fat has a similar fatty acid composition as coconut and palm oil, making it one of the most promising alternative fat sources for the food industry, where these lipid sources are used in a large number of processed foods [136].

The antimicrobial capacity of BSFL oil has been studied and demonstrated in *in vitro* studies against Gram-positive and Gram-negative bacteria [139, 174]. The antimicrobial capacity of BSFL is due to its high concentration of lauric acid [14]. The mechanisms of lauric acid antimicrobial processes are still being studied, but three have been described: 1) destruction of the cell membrane of gram-positive bacteria and lipid-coated viruses by physicochemical processes, 2) interference with cellular processes, such as signal transduction and transcription, and 3) destabilization of cell membranes [175], through inhibition of the enzyme MurA [176]. Very few *in vivo* investigations have been performed in animals to study the antimicrobial property of BSFL. The inclusion of BSFL oil in the diet does not affect the microbiota, improves intestinal morphology, and increases beneficial microorganism populations [140–142].

BSFL oil has the ability to regulate blood cholesterol levels due to its lauric acid content. In an *in silico* study animals fed lauric acid had increased cholesterol metabolism due to reduced HMG-CoA enzyme activity [177]. BSFL oil may also affect markers and coagulation factors, inhibiting platelet aggregation, prolonging the activated partial thromboplastin time. In *ex vivo* and *in vivo* studies, the compounds extracted

*Perspective Chapter: Technological Strategies to Increase Insect Consumption – Transformation… DOI: http://dx.doi.org/10.5772/intechopen.108587*

#### **Figure 2.**

*Appearance of traditional insect ingredients, BSFL oil (A) and BSFL meal (B) and new insect-based ingredients, such as emulsions (Ai-Aiv [167, 168]), nanoemulsions (Av, [137]), protein extracts (Bi, [169]), protein concentrates (Bii, [170]), alginate-insect meal beads (Biii, [156]), micro-powders (Biv, [155]), and aqueous extracts (Bv, [171]).*

from three insects, *Protaetia brevitarsis* seulensis, *Tenebrio mollitor* and *Oxya chinensis* sinuosa, succeeded in reducing platelet aggregation and the rate and size of arterial and pulmonary thrombus formation in mice [160–162].

Studies on new ingredients based on whole and defatted meals have focused on concentrating protein by developing protein concentrates, protein isolates, protein hydrolysates, and protein fermentates, using methods such as alkaline extraction and isoelectric precipitation (**Table 2**). The development of protein concentrates and protein isolates is focused on because i) protein is one of the most expensive nutrients in human and animal diets; and projections indicate that the price of protein ingredients of animal and plant origin will increase steadily [22]. ii) Proteins of animal origin are complex to replace in human and animal diets and are not very sustainable [178, 179]. Insect proteins represent a sustainable replacement alternative to animal proteins [180, 181]. iii) The protein content of insect meals, especially defatted meal, is very high (**Table 1**) and similar to meals of vegetable

origin (40–55%), meat/bone meal (40–50%), and offal (40–60%) [182]. The protein content of defatted cricket, mealworm, and BSFL meal is similar to meals of marine origin such as fish meal (60–75%) [182]. iv) The protein quality of insects, in terms of essential amino acid content (good source of lysine, methionine, threonine, leucine, alanine, valine) and amino acid digestibility (80–93%), is excellent. v) Insect proteins tend to be high in glutamic acid, which is the main amino acid in BSFL and mealworm meal [48], and is related to umami taste, highly preferred by animals and humans [183, 184]. vi) Insect proteins have technological properties suitable for the processing of certain foods such as meat substitutes [185], jerky meat analog [186], extruded cereals [153], rusks [187], and pastas [188]. vii) Products that concentrate insect proteins as concentrates and isolates have better sensory properties than insect meals, such as lighter colors [65], better taste [64], better volatile profile [149], and better emulsifying and foaming properties [98, 102]. Insect protein concentrates and isolates have been used in human food and are commercially available. Some examples are Becrit® and Trillions®, under the concept of protein shakes; Isaac nutrition®, protein powder; AdalbaPro IPC®, protein concentrate; and AdalbaPro FTIP®, protein concentrate powder with fiber texture. **Figure 2** shows that the main change in appearance of protein concentrates (**Figure 2Bi-ii**), made from insect meals (**Figure 2B**), is a lighter coloration of the brown shades of the meals.

Hydrolysates and fermentates have been developed for the purpose of reducing some antinutritional factors of insect meals such as chitin [149], improving organoleptic properties, increasing shelf life [189, 190], providing antioxidant properties [149, 191, 192], increased nutrient digestibility, production of antimicrobial substances, and health-promoting molecules [149]. Enzymatic hydrolysis using a variety of enzymes, such as alkalase, papain, peptidase, protease; and alcalase, papain, peptidase, protease; and biological hydrolysis using yeasts (*Yarrowia lipolytica* and *Debaryomyces hansenii*) have been studied to obtain peptides with bioactive properties and to improve protein digestibility, mainly. Fermentation of insect meal with lactic acid bacteria or yeast (*Saccharomyces cerevisiae*) has been used to improve sensory properties, mainly by modifying the volatile profiles, decreasing indole, pyrazines, 1-octen-3-ol, and 3-octanol, and increasing propanol, ethanol, acetone and 2-butanone, reducing fecal, toasted, earthy, mushroom, and bitter taste [157, 158].

Other technologies applied to develop new ingredients have been extrusion to produce pellets and snacks based mainly on insect meal mixed with cereals. The main result has been the increase in the digestibility of some nutrients such as protein and starch. In these studies, it was indicated that the insect meal content used alters some important properties of the extruded products (**Table 2**). This technology has been widely used for the development of complete foods and snacks for dogs and cats [48]. Some examples are Eat Small Mindfulness®, Brit Care Immunity®, CircularPet®, Yora®, Insecta®, buggybigs®.

Encapsulation is a technology widely used in the food industry, especially spray drying [193], because it improves the sensory characteristics of the compounds to be encapsulated [194]. In addition, controlled release formulations can be developed to add the encapsulated compounds in complex foods such as yogurt, beverages, dairy, and others [195–197]. Although, this technology is widely used to improve the sensory properties of ingredients, it has not been thoroughly studied for encapsulating insect meal and oil. Among the existing works, spray drying has been used to develop insect meal micro-powders (**Figure 2Biv**), which presented better appearance and color (similar to wheat flour), better texture (with smaller particle size), and better aroma than unencapsulated house fly larvae meal (**Table 2**). However, the protein content of

#### *Perspective Chapter: Technological Strategies to Increase Insect Consumption – Transformation… DOI: http://dx.doi.org/10.5772/intechopen.108587*

the micro-powders was low at about 5.1 g per 100 g of powder, whereas the meal that gave rise to the micro-powders contained 54 g of protein per 100 g of flour. Even so, micro-powders are considered a "source of protein" according to the Codex Alimentarius [198]. The challenge for this technology is to concentrate on the nutrients, especially protein, from insect meals, being able to use previously described technologies such as protein isolates and concentrates. In another study, house fly meal was encapsulated by ionic gelation, obtaining alginate-insect meal beads with an appearance similar to black "caviar" (**Figure 2Biii**), with better aroma than the unencapsulated meal (**Table 2**). The application of this type of product in human food is complex, due to the rejection that its appearance could cause, but it is possible to incorporate it as food for exotic pets (such as water turtles, fish, ferrets, hedgehogs), which consume live and dehydrated insect larvae [48]. The pet industry has a high level of innovation in food products and consumption of innovative foods and snacks is on the rise [199, 200].

In **Table 2**, the development of oil nanoemulsions is described. The technique is considered an encapsulation process, since the oil is protected and separated from the water by a dynamic surfactant layer formed by emulsifying agents. This technique has been widely used in the food industry for the following reasons: 1) to improve the stability of some lipophilic active compounds such as vitamin D3 [201], carotenoids [202], and α-tocopherol [203], 2) to improve the absorption, bioavailability, and bioactivity of lipophilic bioactive compounds with low absorption such as curcumin [204] and astaxanthin [205], and 3) to provide the ability to release encapsulated actives in a controlled manner [206, 207].

The functional properties of insect-based food ingredients, such as antioxidant capacity, antimicrobial activity, inhibition of platelet aggregation, enzymatic inhibition, and antidiabetic potential, have been less studied than their nutritional properties as food ingredients [208, 209]. The literature shows that ingredients obtained from insects such as aqueous extracts [125], meals [191, 210, 211], and proteins and peptides [126, 212, 213], exhibit high antioxidant capacity, so they could have potential use in health disorders associated with oxidative stress [214]. The antioxidant capacity is due to the presence of phenolic compounds, proteins, peptides, chitin, fatty acids, and others [215, 216].

A great diversity of bioactive compounds has been isolated from insects, such as free fatty acids, amino acids, organic acids, carbohydrates, hydrocarbons, sterols, and others [125]. The methodologies for their extraction have been ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE), using ethanol or a mixture of ethanol and water [125] (**Table 2**). The appearance of these extracts is presented in **Figure 2Bv**, observing different colorations that depend on several factors, such as concentration of the extracts and extraction technique. Extracts have anti-inflammatory, antimicrobial, antiangiogenic, antiproliferative, and antioxidant properties. The ability to inhibit the activity of certain enzymes has also been studied. In *in vitro* studies, extracts of *A. domesticus* and *T. molitor* were able to inhibit pancreatic lipase [125]. These extracts could have an application in the treatment and prevention of obesity [217]. Proteins from the insects such as *B. mori*, *T. molitor*, *Alphitobius diaperinus*, and *Gryllus bimaculatus* [218–221] were able to inhibit angiotensin-converting enzyme (ACE), dipeptidyl peptidase-4 (DPP-IV) [220], and α-glucosidase activity [218, 221], with antidiabetic potential. In animal studies, supplementation with ethanolic extract of *B. mori* improved glycemic status in obese mice with type 2 diabetes, reducing glycemia and restoring pancreatic functionality [222, 223]. Soluble extracts obtained from 12 insect species showed antioxidant activity, the highest in extracts from grasshoppers, silkworms, and crickets [216]. Antioxidant activity was also found in aqueous extract of *Vespa affinis* L. [214]. Antibacterial substances

such as N-beta-alanyl-5-S-glutathionyl-5-S-glutathionyl-3,4-dihydroxyphenylalanine from *Sarcophaga peregrina* and p-hydroxycinnamaldehyde from *Acantholyda parki* larvae were isolated from extracts of immunized insects [224, 225].

Other insect-based functional compounds extensively studied in the recent years are antimicrobial peptides (AMPs), which are extracted and purified by different technologies, such as reverse phase high-performance liquid chromatography (RP-HPLC), DNA extraction, RNA extraction, fast performance liquid chromatography (FPLC), and gel filtration chromatography [226] (**Table 2**). AMPs are peptides with low molecular weight, high thermal stability, and a broad antimicrobial spectrum [227, 228]. A large number of AMPs derived from *Acalolepta luxuriosa*, *A. mellifera*, *B. mori*, *Galleria mellonella*, *Heterometrus spinifer*, *Holotrichia diomphalia*, *Hyalophora cecropia*, *Oxysternon conspicillatum*, *Pandinus imperator*, and *Sarcophaga peregrine* have been investigated and are effective against a wide range of Gram-negative and Gram-positive bacteria [229, 230]. Their mechanism of action depends on the type of AMP and the target pathogen. AMPs can interact with the microbial membrane surface, alter permeability and induce cell lysis, enter the cell, and damage bacterial components such as DNA and RNA, and promote the bacteriostatic effects [226, 228]. The use of AMPs as an alternative to antimicrobials in human and animal health could help reduce antimicrobial resistance [228].

The challenge for the future of insects as food for humans and animals is to increase research on technologies that can be used to transform common insect-based ingredients such as meal and oil into ingredients with higher added value, functional properties, and optimal sensory properties for greater acceptance and consumption of insects by humans, so these ingredients can be included in a greater number of foods.
