Goutam Roy Chowdhury1, Upasana Datta2, Sufia Zaman2 and Abhijit Mitra3*
Received: July 15, 2017; Published: July 31, 2017
Corresponding author: Abhijit Mitra, Department of Marine Science, University of Calcutta, 35 B.C. Road, Kolkata 700019, India
Insects comprise the most diverse group of multicellular organisms in the planet Earth, which provide several ecosystem services like pollination, pest control (bio-control), decomposition, transference of energy through food chain etc. In addition, insects are widely used today as human edible items and ingredients of fish-feed, turtle-feed, livestock, etc. In this paper we focus on the vital ecosystem services provided by insects with special reference to their services in the domain of human food. Our research stands on the high nutritional value of insects preferably protein which ranges between 13% - 77%. Our paper has two-fold goals namely documentation of selective ecosystem services of insects and highlighting the edible value of insects. In this paper we have intentionally excluded the value of commercially produced insectderived products like honey, wax, silk, shellac, etc. rather our main focus is to highlight the nutritional value of insects which is the most demanding subject to feed the rapidly rising population in the present world.
Insects play an important role in the reproduction of plant species. About one lakh pollinator species have been identified out of which 98% are insects . Over 90% of two lakh fifty thousand flowering plant species depend on pollinators. This is applicable for 75% of the hundred crop species that generate most of the worlds’ food grain.
The process of waste biodegradation is regulated and controlled by the insect community. Beetle larvae, flies, ants and termites clean up dead plant matter and break them into finer particles for further decomposition by microbial community. Dung beetles (about 4000 species documented) also play a significant role in decomposing manure. If the dung remains on the soil surface about 80% of the nitrogen (N2) is lost to the atmosphere which is one of the prime causes of global warming.
Pest control is a vital aspect in the domain of agriculture and in most of the cases it is done by using chemicals. This not only harms the environment, but also decreases the productivity of the soil. Today there is an inclination of biological control of harmful insects. The number of insects that feed or prey on other insects is vast. 10% of all insects are parasitoids . Entire orders of insects - such as Odonata (dragon flies) and Neuroptera (net-winged insects such as lacewings and ant lions) - are predators. A large percentage of true bugs (Hemiptera), beetle (Coleoptera), flies (Diptera) and wasps, bees and ants (Hymenoptera) are also predators. The number of beneficial insect species in the average agro-ecosystem typically far outweighs the number of harmful insect species.
Table 1: Comparison of average protein content among insects, reptiles, fish and mammals.
Table 2: Examples of energy content of differently processed insect species, by region.
The world population as of now is 7, 518,254,096 as per the record of 02:35 pm Indian Standard Time (IST) of 14th July, 2017. It is expected that 2050, the projected world population is 9.8 billion and 11.2 billion during 2100 . This enormous population needs food supply on regular basis for their survival and growth. The land and aquatic resources have already reached the critical level and under this circumstance insects can provide an alternative food source as they are rich in protein and other minerals (Table 1). In addition, insects also provide dietary energy (Table 2).