Insects as food and feed: nutrient composition and environmental impact

Abstract Because of an increasing world population, with more demanding consumers, the demand for animal based protein is on the increase. To meet this increased demand, alternative sources of animal based protein are required. When compared to conventional production animals, insects are suggested to be an interesting protein source because they have a high reproductive capacity, high nutritional quality, and high feed conversion efficiency, they can use waste as feed and are suggested to be produced more sustainably. This thesis starts with a historical perspective on insects as food and feed, and explains why insects are expected to be more suitable production animals. In Chapter 2 the nutritional quality of insects is discussed based on a variety of insects that are commonly used as feed or food. Additionally, various environmental and dietary factors which are known to significantly affect insect chemical composition are reviewed. In Chapter 3 the direct production of greenhouse gases (GHG) and ammonia, as well as carbon dioxide emission and average daily weight gain of five insect species is quantified. Differences regarding the production of GHGs (expressed as CO2 equivalents) between insect species were mainly due to the production of methane. All species tested emitted lower amounts of GHG than cattle, had a higher growth rate than cattle or pigs, and emitted lower amounts of ammonia and either comparable or lower amounts of GHG than pigs. Results from Chapter 3 were used in a Life Cycle Assessment conducted in Chapter 4. For a mealworm production system total GHG production, energy use, and land use were quantified and compared to conventional sources of animal protein. This chapter shows that mealworms should be considered a more sustainable source of edible protein, and that a large part of their environmental impact is due to the feed they consume. In Chapter 5 four diets composed from industrial organic by-products were formulated such that they varied in protein and fat content. These diets were offered to four insect species and their feed conversion efficiency was determined. Diets used in large scale production systems were included and served as controls. Diet composition affected feed conversion efficiency in all species. It is concluded that the four investigated species are efficient production animals and can therefore be considered interesting for the production of feed or food. Furthermore, diet composition affected insect composition, indicating possibilities to tailor the composition of these insects to best meet consumers’ needs. In Chapter 6 the suitability of chicken, pig, and cow manure was compared as feed for larvae of the Black Soldier Fly, which in turn could be used as feed for conventional production animals. Newly hatched larvae were directly inoculated on moistened manure. Whereas survival was high on all three tested substrates, the development time was greatly prolonged compared to the control diet. On pig manure, more nitrogen was utilised than on chicken and cow manure, while P utilisation was highest on cow manure. A large proportion of manure nitrogen was lost in all treatments, indicating that the production system would require a way to prevent this in order to make it ecologically sound. Furthermore, to improve economic viability, shorter development times would be required. In Chapter 7 the suggestions why insects would make suitable production animals are evaluated based on both literature data, and data gathered in this thesis. Furthermore, prospects for insects as food or feed are put forward, with emphasis on the knowledge and legislation requirements for the further development of the insect production sector.</p

Environmental Impact of the Production of Mealworms as a Protein Source for Humans - A Life Cycle Assessment

The demand for animal protein is expected to rise by 70–80% between 2012 and 2050, while the current animal production sector already causes major environmental degradation. Edible insects are suggested as a more sustainable source of animal protein. However, few experimental data regarding environmental impact of insect production are available. Therefore, a lifecycle assessment for mealworm production was conducted, in which greenhouse gas production, energy use and land use were quantified and compared to conventional sources of animal protein. Production of one kg of edible protein from milk, chicken, pork or beef result in higher greenhouse gas emissions, require similar amounts of energy and require much more land. This study demonstrates that mealworms should be considered a more sustainable source of edible protein

Insects as food and feed: nutrient composition and environmental impact

Abstract Because of an increasing world population, with more demanding consumers, the demand for animal based protein is on the increase. To meet this increased demand, alternative sources of animal based protein are required. When compared to conventional production animals, insects are suggested to be an interesting protein source because they have a high reproductive capacity, high nutritional quality, and high feed conversion efficiency, they can use waste as feed and are suggested to be produced more sustainably. This thesis starts with a historical perspective on insects as food and feed, and explains why insects are expected to be more suitable production animals. In Chapter 2 the nutritional quality of insects is discussed based on a variety of insects that are commonly used as feed or food. Additionally, various environmental and dietary factors which are known to significantly affect insect chemical composition are reviewed. In Chapter 3 the direct production of greenhouse gases (GHG) and ammonia, as well as carbon dioxide emission and average daily weight gain of five insect species is quantified. Differences regarding the production of GHGs (expressed as CO2 equivalents) between insect species were mainly due to the production of methane. All species tested emitted lower amounts of GHG than cattle, had a higher growth rate than cattle or pigs, and emitted lower amounts of ammonia and either comparable or lower amounts of GHG than pigs. Results from Chapter 3 were used in a Life Cycle Assessment conducted in Chapter 4. For a mealworm production system total GHG production, energy use, and land use were quantified and compared to conventional sources of animal protein. This chapter shows that mealworms should be considered a more sustainable source of edible protein, and that a large part of their environmental impact is due to the feed they consume. In Chapter 5 four diets composed from industrial organic by-products were formulated such that they varied in protein and fat content. These diets were offered to four insect species and their feed conversion efficiency was determined. Diets used in large scale production systems were included and served as controls. Diet composition affected feed conversion efficiency in all species. It is concluded that the four investigated species are efficient production animals and can therefore be considered interesting for the production of feed or food. Furthermore, diet composition affected insect composition, indicating possibilities to tailor the composition of these insects to best meet consumers’ needs. In Chapter 6 the suitability of chicken, pig, and cow manure was compared as feed for larvae of the Black Soldier Fly, which in turn could be used as feed for conventional production animals. Newly hatched larvae were directly inoculated on moistened manure. Whereas survival was high on all three tested substrates, the development time was greatly prolonged compared to the control diet. On pig manure, more nitrogen was utilised than on chicken and cow manure, while P utilisation was highest on cow manure. A large proportion of manure nitrogen was lost in all treatments, indicating that the production system would require a way to prevent this in order to make it ecologically sound. Furthermore, to improve economic viability, shorter development times would be required. In Chapter 7 the suggestions why insects would make suitable production animals are evaluated based on both literature data, and data gathered in this thesis. Furthermore, prospects for insects as food or feed are put forward, with emphasis on the knowledge and legislation requirements for the further development of the insect production sector

Environmental impact of insect rearing

This chapter discusses the environmental impact of insect rearing. Direct greenhouse gas (GHG) emissions from insects used as feed or food are discussed and data from life cycle assessments (LCAs) on commercially farmed insects are discussed per species. The relevance of the utilized feed on the environmental impact of insects and their derived products, including suggestions to lower this impact are also discussed. It is concluded that land use associated with insect production generally seems low, compared to conventional feed and food products. The EU (expressed as fossil fuel depletion) of insect production is often high compared to conventional products. To a large extent this is because several LCAs have been conducted for systems in temperate climates, which require extensive climate control

Insects as food for insectivores

A variety of insects are commonly fed to captive insectivores. We review the nutrient content of a variety of commercially raised insects and compare those values to the data available for wild insects. These data are discussed in light of the nutrient requirements for domestic animals to identify nutrients of concern for captive insectivores. Additionally, various environmental and dietary factors that can significantly affect insect nutrient composition are reviewed. We then evaluate the various techniques that are currently used to enhance the nutrient content of commercially bred insects, including gut loading and dusting. Lastly, possible negative considerations that might be important factors when feeding captive insectivores, including pathogens, pathogenic microorganisms, toxins, and antinutritional factors, are discussed

Nutritional value of insects and ways to manipulate their composition

This article reports on the nutrients present in insects and factors affecting their variability. Data on protein content and amino acid profiles of a variety of insect species are discussed and their amino acid profiles compared to nutrient requirements of growing broiler chicks, catfish, trout, swine, and human adults and young children. Both in vitro and in vivo protein digestibility data for a variety of insect species is presented and factors affecting these data are discussed. Furthermore, the fat content and fatty acid profiles of a variety of insect species is reviewed, with special attention on omega-6 and omega-3 fatty acids. Information on carbohydrates, fibre and chitin in insects is shown along with potential effects on nutrient availability. This is followed by a discussion of essential minerals in insects with an emphasis on calcium and phosphorus. Data on insect vitamin content is shown along with a discussion of antinutritional factors such as phytate and thiaminase, which can adversely affect their nutritional value. Dietary effects on insect nutrient composition are reviewed with an emphasis on essential minerals, heavy metals, vitamin E, and carotenoids. Lastly, the effects of processing, including protein extraction and various cooking methods on insect composition are discussed. In summary, this article provides an overview of the nutrient content of insects, and how select nutrients can be altered

Carrot supplementation does not affect house cricket performance (Acheta domesticus)

The demand for house crickets as a source of food or feed is increasing. Meeting this demand will require efficient production systems. House crickets are often fed a combination of dry feed and fresh plant material. Supplying fresh plant material could improve growth and development, but also increases labour and costs. Two experiments were conducted to verify that provision of fresh plant materials has a beneficial effect on house cricket performance. In the first experiment, house crickets were provided with an ad libitum supply of chicken feed, a water dispenser, and with carrots at different frequencies: (1) daily; (2) three times a week; (3) first week daily then three times a week; (4) two weeks daily then three times a week; and (5) no carrots. When the first cricket in a container reached adulthood, all crickets in that container were harvested. Survival, development time and body weight were determined. In a second experiment feed conversion efficiency of house crickets, either provided with carrots daily or not at all, was compared. No effects of carrot provision on survival, development time, body weight or feed conversion efficiency were found. The outcomes of these parameters were similar to other studies in which crickets were provided with chicken feed. The results indicate that supplying carrots in addition to a suitable dry feed and water does not improve house cricket survival, development time, body weight and feed conversion efficiency.</p

Gaan we insecten houden in plaats van kippen en varkens?

Het eten van insecten lijkt alleen maar voordelen te hebben vergeleken met het consumeren van vlees of vis. Massaal overgaan op het kweken en eten van insecten is dus ideaal, zou je zeggen. Dennis Oonincx, onderzoeker aan de Universiteit van Wageningen, doet samen met collega's onderzoek naar insecten. Ze kijken of insecten een alternatief zijn voor ons stukje kip of varkensvlees