Reasons will be given why insects as a food and feed source is a serious alternative to conventional meat products and feedstocks, such as fishmeal. First the nutritional value of insect will be discussed.
Due to the large variety of insect that can be eaten, more than 2,000, drawing generalisations can be quite difficult. Besides, there are many factors that have an influence on nutritional values: such as life stage harvested, diet, and environmental factors such as temperature, humidity, and photoperiod (Finke and Oonincx, 2014). Rumpold and Schlüter (2013) reviewed the nutritional composition of a large number of edible insect species and concluded that the data were subject to a large variation that many insect species meet amino acid requirements for humans, are high in monounsaturated fatty acids and polyunsaturated fatty acids, and rich in several micronutrients such as copper, iron, magnesium, manganese, phosphorous, selenium, and zinc as well as riboflavin, pantothenic acid, biotin, and in some cases folic acid. Payne et al. (2016) determined the nutrient value score of crickets and mealworms had a significant higher nutritional value than the commonly consumed meats beef and chicken. In their analyses, not a single comparison showed the insect species (crickets, honeybee, silkworm, mopane caterpillar, mealworms, palm weevil larvae) to be nutritionally inferior to beef, chicken or pork. The high iron and zinc content of many insect species (Latunde-Dada et al., 2016) is interesting considering the high incidence of anaemia and zinc deficiencies in the world. For example, in the Democratic Republic of Congo infants who consumed a caterpillar cereal had higher haemoglobin concentration and fewer were anaemic (Bauserman et al., 2015).
Chitin, the exoskeleton of insects, has shown to have an interesting role, in particular with regard to immune responses (Lee et al., 2008; Muzzarelli, 2010; Reese et al., 2007), among other in relation to asthma and allergy (Brinchmann et al., 2011). Using chitin from shrimps, Khempaka et al., (2011) fed broilers with up to 15% shrimp meal and the result was increased populations of intestinal Lactobacillus and decreased intesatinal Escherichia coli and cecal Salmonella. Humans likely have chitinase in their gastric fluids (Paoletti et al., 2007).
Insects produce less ammonia and GHG than conventional livestock (Oonincx et al., 2010). Using a life cycle analyses, production of one kg of edible protein from milk, chicken, swine, or beef resulted in higher GHG emission than mealworms and it required much more land, while similar amounts of energy were required (Oonincx and De Boer, 2012).