Fish production, processing and consumption are one of the major contributors of organic wastes. Fish is processed into fillets, chips, protein products, canned foods, and fish oils. A big proportion of fish products is meant for human consumption. As the demand for fish products continues increasing, the production of fish also increases, and so does the waste produced during processing and after. Some of these wastes from fish include fish bones, leftovers, and dried fish. The increased rate of fish waste generation has become of due concern following its environmental impact which involves bad odour. This article shall briefly describe the lifecycle of fish waste and how it is improvised to become useful
According to the Food and Agricultural Organisation (FAO), about 50% of the caught fish is used for human consumption, and the rest of it is wasted (Fao, n.d.). Thus, significant amounts of waste products or the rest of the raw materials are discarded, thereby creating undesirable impacts on the environment. Often, fresh fish products among other aquatic products are highly perishable and require refrigerated storage to maintain their shelf life and prevent damage to them. If not well stored, these products end up either being disposed or recycled as waste products (Disposal of fish waste, 2016).
Most of us will think that fish waste is the fish bones left over after a meal. However, surprisingly, fish waste includes the organic waste such as the fecal material and from the fish farms and other fish rearing points. Often, these wastes contaminate the water that often find its way into the natural environment. As a result, waters from the surrounding will experience accelerated, and uncontrolled growth of algae, that could be deadly for some marine life and indirectly be a danger to human beings (Lê, 2011).
Despite its adverse environment effect, fish waste could be utilised in various ways to be of economic and environmental benefit. There exist three most common ways of this utilisation, and that include the manufacture of fish oil/meal, manufacture of fertiliser, and production of silage (Gálvez and Bergé, 2013). For long, fish waste has been refined using commination and heating to separate oil. The remaining solid material is then used as a fish meal, a common agricultural feed ingredient. However, even though these methods could be deemed traditional, other modern methods have been implemented successfully while others are being tested (Yahyaee, Ghobadian and Najafi, 2013). For instance, the production of biodiesel has been shown to be catalysed by fish bone products. Other uses include the manufacture of fine chemicals used in human health and nutrition, animal feed and health, and industrial enzymes. Thus, fish waste, if well utilised could be beneficial environmentally, economically, and physiologically (Korres, O’Kiely, Benzie and West, 2013).
While the world increasingly consumes more and more fish, so has the amount of fish waste continued increasing? As discussed in this blog, if not well disposed of, fish waste could impact the environment negatively. However, through the available methods of utilisation, fish waste could be turned into useful products. Fish waste has for long been processed into fish oils and meals. Additionally, modern methods have seen newer uses of the wastes such as biodiesel and chemical production.
Disposal of fish waste 2016, Netregs.org.uk. viewed 9 June 2016, <http://www.netregs.org.uk/library_of_topics/waste/more_waste_materials_topics/disposal_of_fish_waste.aspx>.
Fao n.d., Waste from processing aquatic animals and animal products – 3. Aquatic waste treatment and utilization. viewed 9 June 2016, <http://www.fao.org/docrep/003/x9199e/X9199E04.htm>.
Fish wastes – Fish oil products – Fish production 2009, Enerfish.eu. viewed 9 June 2016, <http://www.enerfish.eu/p-techno-techno_id-1/fish-wastes-to-fish-oil.html>.
Gálvez, R. and Bergé, J. 2013, Utilization of fish wastes, CRC Press, London.
Korres, N., O’Kiely, P., Benzie, J. and West, J. 2013, Bioenergy production by anaerobic digestion : using agricultural biomass and organic wastes,.
Lê, M. 2011, Nutrition, Food Science, and Dietetics Faculty Have Information Needs Similar to Basic and Medical Sciences Faculty – Online Access to Electronic Journals, PubMed/Medline, and Google, Evidence Based Library and Information Practice, vol 6, no 4, p.155,.
Yahyaee, R., Ghobadian, B. and Najafi, G. 2013, Waste fish oil biodiesel as a source of renewable fuel in Iran, Renewable and Sustainable Energy Reviews, vol 17, pp.312-319,