Abstract
In this study, a self-selected feed design was conducted for Japanese food wastes, considering the macronutrients (protein, lipid, carbohydrate) and six feed options and three options for vegetable wastes, and performance was compared with commercial diet to determine the usefulness of the feed design method and the possibility of using food waste in Japan were examined by comparing the performance of the feed design method with commercial diet. Data on self-selection diet design for crickets at different growth stages were obtained to determine the differences in feed consumption rates and nutrient requirements among stages. The results showed that it is possible to achieve cricket weight and feed conversion efficiencies (0.5-0.8) comparable to those of commercial diets using food residues when macro-nutrients are considered, and abundant options are provided. On the other hand, the use of only vegetable wastes resulted in lower cricket weight and higher feed conversion efficiency (0.8-1.4). Based on feed consumption rates, bread bran, rice bran, and fish meal were found to be suitable feeds among Japanese food waste for production in all growth stages, while bean curd and sake less were found to be suitable for production in some growth stages. Data obtained from self-selections separated by growth stage revealed that the percentage of feed consumption varied greatly among growth stages, being about 50-68% in the late growth stage. Percentages of macronutrients and micronutrients were also found to vary by growth stage. Protein percentages were found to be higher in the second week after hatching. Lipids were highest in the first week and decreased thereafter. Crude fiber was lowest in the fourth week. Ash content did not change significantly at all stages. This research is the first attempt at self-selection of crickets in different growth stages, and the data obtained can contribute to feed design.
Abstract
The yellow mealworm, Tenebrio molitor L. (Coleoptera: Tenebrionidae), is one of the few edible insects commercially produced around the globe as alternative protein sources for food and feed. Temperature and nutrition are the two most influential environmental determinants of growth and development in insects, but little is known about their combined effects in T. molitor. Here we examined how temperature and dietary protein:carbohydrate (P:C) balance act in concert to influence key performance traits in T. moltior larvae reared on one of the 36 treatment combinations of six temperatures (19, 22, 25, 28, 31, and 34 °C) and six protein:carbohydrate ratios (P:C = 1:5, 1:2, 1:1, 2:1, 5:1, and 1:0). Apart from females accumulating higher lipid content than males, there were no sex differences in all measured traits. Survivorship was high at low temperatures (<25 °C) and high P:C ratios (>1:1), but decreased with increasing temperature and decreasing P:C ratio. An increase in temperature accelerated development but resulted in reduced pupal mass. Thermal optimum for pupal mass (19.3 °C) was thus much lower than that for development time (28.1 °C). Growth rate peaked at 27.9 °C and P:C 1.65:1 and decreased as both temperature and P:C ratio deviated from their optimum. All four key performance traits (survivorship, development time, pupal mass, and growth rate) were expressed at high levels and, hence, optimized at temperatures between 25.7 °C and 27.4 °C and P:C ratios between 1.17:1 and 2.94:1. Food consumption rate was the highest at a high P:C ratio of 8.4:1, whereas post-ingestive food utilization was the most efficient at a moderate P:C ratio of 1:1.27. The rate and efficiency of food processing were optimized at temperatures between 24.5 °C and 29.9 °C and P:C ratios between 1:1.01 and 3.98:1. Our results have implications for improving the production and nutritional value of T. molitor larvae.
Abstract
In Africa, food insecurity seems to be a continual problem as a result of various factors such as extreme poverty, water scarcity, land degradation, and climate change. As a result, chronic hunger and malnutrition are still prevalent in many African countries. Consequently, the utilization of available and affordable natural food sources is needed to accommodate the energy and nutritional requirements of the people, such as edible insects. Edible insects are abundant and locally available throughout Africa, hence could be utilized as low-cost, nutritious, and sustainable foods. Around 500 species have been recorded in sub-Saharan Africa out of the 2,100 known edible insect species worldwide. The consumption of insects, also known as entomophagy, has been historically practiced by indigenous people of Africa. To date, edible insects are seen in Africa as a good opportunity, particularly for rural households, to improve their livelihoods at an economic and nutritional level. Edible insects are a great source of energy and nutrients – and their rearing only requires a small amount of water, land and feeding resources. Entomophagy may also serve as an ecologically sound control measure for insect pests, such as locusts, that periodically wreak havoc on agricultural fields. The combination of being a highly nutritious food source and having economic advantages made edible insects very attractive in all the African regions. Their promotions into the diet would ameliorate the well-being of the population and boost economic growth in Africa. However, African countries need local and regional legal frameworks to achieve smooth functioning of marketing of edible insects and their products.
Abstract
Separation of Tenebrio molitor larvae from unwanted residues, like frass, feed or exuviae is a key process step for an industrial scale plant. One method to separate larvae from residues is using a zigzag air classifier. For designing and for an efficient operation of a zigzag air classifier, the terminal velocity is a key parameter to separate larvae from different residues with a high separation sensitivity. In this work, the terminal velocities of different larvae sizes are evaluated analytically, numerically and experimentally. For this, the sizes of 3 week to 12 week old larvae were used to calculate and simulate the terminal velocity. To validate the results, an experiment was carried out and compared with the analytical and numerical data. For this, a model for T. molitor larvae was designed to calculate the surface and volume of a larva to produce equivalent spheres with the same physical properties as a real larva. The results are showing similar curves with terminal velocities from 5 m/s for young larvae (3 weeks old) to 12 m/s for older larvae (12 weeks old). The deviations between each method are 1 m/s for smaller larvae and 1.5 m/s for bigger larvae. In further experiments and simulations, approaches with calculation methods for non-spherical particles are necessary to achieve results closer to reality due to the cylindrical shape of T. molitor larvae.
Abstract
As the global population continues to grow, traditional protein sources like meat and fish are becoming increasingly unsustainable due to their environmental impact. Edible insects, on the other hand, are highly nutritious, require minimal resources to produce, and emit significantly fewer greenhouse gases than traditional livestock. Lepidoptera, one of the most diverse insect orders, contains some popular edible species that have been consumed traditionally for centuries across the globe. Based on this review, about 24 families with a total of about 350 edible lepidopteran species were recorded. They are often praised for their excellent nutritional value, such as having high protein and healthy fat content. Edible lepidopterans also contain minerals, essential amino acids, and vitamins, making them a nutritious addition to a balanced diet. They also contain bioactive compounds which have various nutraceutical and pharmaceutical properties. Furthermore, some edible lepidopterans can be farmed and require minimal space and resources. However, there are significant challenges associated with their use as food. One of the primary challenges is the lack of regulations governing their production and distribution, which creates uncertainty for consumers and businesses alike. Consumer acceptance is also a significant barrier to the widespread adoption of insects as food. To overcome these challenges, there is a need for clear regulations that ensure the safety and quality of insect-based products. Furthermore, it is important to raise awareness about the nutritional and environmental benefits of edible insects as sustainable food for the future to promote their acceptance among consumers.
Abstract
This study estimated the effects of replacing fish meal (FM) with defatted Periplaneta americana meal (PAM) on the growth, antioxidant status, immunity, and hepatic and intestinal health of juvenile Nile tilapia (Oreochromis niloticus). Five diets were formulated by replacing 0% (PAM0), 25% (PAM25), 50% (PAM50), 75% (PAM75), and 100% (PAM100) of FM, and then fed to triplicate groups of 15 fish (10.58 ± 0.73 g) for 60 days. The results indicated that growth and feed utilisation were increased in the PAM25 group while decreased in the PAM100 group (
Abstract
Product safety is a major concern when using edible insects and insect-derived products due to insects’ diverse microbial community. Therefore, development of reliable post-processing treatments are required. Commonly used thermal treatments are effective against microorganisms but can have negative effects on product quality and nutritional value. Low-energy electron beam (LEEB) is an emerging non-thermal surface treatment technology for microbial decontamination of low water activity goods while preserving product quality. However, its potential application as an insect post-processing treatment has not been explored. To assess the effectiveness of LEEB treatment (250 keV and 12 kGy), three separate experiments were conducted with dried black soldier fly larvae (BSFL) and yellow mealworm (YMW). First, to assess LEEB’s potential in inactivating microorganisms in insect products, LEEB treatment was conducted on dried BSFL inoculated with Escherichia coli K-12. Secondly, the effect of LEEB treatment on reducing naturally occurring microbial populations after microwave drying was evaluated. Finally, a six-month controlled shelf-life study (24 °C, 65% RH) was conducted to assess the long-term efficacy of LEEB treatment by monitoring physical, chemical and microbiological parameters. LEEB achieved a 4-log10 reduction of inoculated E. coli K-12 on dried BSFL and was effective in reducing numbers of all microbiological parameters (aerobic and anaerobic counts) in YMW. Specifically, in non-inoculated samples, aerobic and anaerobic total viable counts (TVC) were reduced by approximately 4-log10 colony forming units per gram (cfu/g) in YMW. In contrast, LEEB treatment moderately reduced microbial numbers in BSFL, with aerobic and anaerobic TVC reduced by approximately 1–2-log10 cfu/g following LEEB treatment. Microbial counts in both BSFL and YMW remained lower than the control throughout the shelf-life. LEEB treatment did not have an influence on the peroxide value. Therefore, LEEB can be an effective and gentle processing technique to support safe dried insect products.
Abstract
The residual population growth imposes an increase in food demand, driving humans to practice agricultural intensification on a large scale. Paradoxically, food and feed production may end up causing various environmental problems. At the same time, about 2.37 billion people in the World currently lack basic food security insurance. As a consequence, alternative sources that can substantially address the demand for food and feed sustainably are needed. Insect farming may offer an environmentally friendly solution for mitigating global food and feed challenges. The article aims to explore the potential of insects as sustainable food and feed sources while assessing their environmental impact, offering innovative solutions for global food security challenges. By highlighting the benefits of edible insects, the article supports informed decision-making and promotes sustainable practices. Mass production of edible insects has seen record growth over the decade, and their demand as future proteins is projected to reach up to 3 million tons in 2030. Additionally, insect farming is evidenced to be economically viable. To meet the demand for edible insects, a breakthrough such as the internet of things can be used to scale up production and processing. However, detailed environmental impact assessments are needed to predict scenarios of large-scale insect farming. Life cycle assessments of some edible insect production systems have validated that insect farming has various beneficial environmental impacts. The utilization of edible insects as food and feed is promising for significantly improving food security and the environmental sustainability of food.
Abstract
Mealworm (Tenebrio molitor) and their derivatives are sustainable ingredients in aquaculture feeds. This study evaluated the effect of fish oil (FO) replacement with mealworm oil (MO) on growth performance, non-specific immune responses and disease resistance against Vibrio parahaemolyticus for Pacific white shrimp (Litopenaeus vannamei). FO in a control diet (Con) was replaced with MO at levels of 25%, 50%, 75% and 100% (designated as MO25, MO50, MO75 and MO100, respectively). A total of 480 shrimp (initial mean body weight, 0.884 ± 0.004 g) were randomly distributed into 20 acrylic tanks (240 L) in quadruplicates groups and fed the experimental diets for 58 days. Growth performance was significantly higher in all MO groups than in Con group. Shrimp fed MO50 and MO75 diets showed significantly improved feed utilisation efficiency than shrimp fed Con diet. Lipid metabolism related-gene expressions of fatty acid binding protein and triacylglycerol lipase in hepatopancreas were significantly downregulated by increment of MO in the diets. Digestibility of protein, lipid, energy and dry matter were not significantly affected by the dietary treatments, while digestibility of poly-unsaturated fatty acids (PUFAs) were significantly decreased by dietary MO supplementation. The levels of n-3 PUFA in muscle and hepatopancreas were significantly decreased with increasing MO levels in the diets. Cumulative survival of shrimp in a challenge test against V. parahaemolyticus was higher in all MO groups and significantly higher in MO25 group than in Con group. Non-specific immune responses were significantly enhanced in all MO groups than in Con group. Replacement of FO with MO in the diets significantly increased haemolymph cholesterol and triglyceride levels. Our findings suggest that MO could be utilised as a promising substitute for FO in the diets of L. vannamei and optimal FO replacement level would be 50% for growth and 25% for disease resistance against V. parahaemolyticus.