Thu. Mar 23rd, 2023
  • Fish processing on Lake Victoria in Kenya generates tons of waste that harms the atmosphere and leads to oxygen depletion and algal blooms that threaten native aquatic species.
  • Science interns at the Kenya Marine and Fisheries Study Institute have created a way to extract useful fish oil from the waste, and they are also producing decorative flowers from fish scales.
  • These innovations are element of a expanding trend of recycling Lake Victoria’s fish waste, turning it into goods that can be sold in regional communities.
  • Scientists aim to decrease the environmental harms of fish waste by means of innovations that could ultimately be scaled up to meet expanding national and international demands for fish oil and other items.

KISUMU, Kenya — At Dunga Beach on the shores of Lake Victoria, quite a few varieties of fish, such as tilapia, Nile perch and mudfish, are processed for consumption and distribution. Every single day right after processing, the fish remains generate tons of waste that threatens the atmosphere.

The method of converting Nile perch into chilled fish fillets for export generates substantial amounts of strong and liquid waste, estimated to be as higher as 50-80% of the original raw material, thereby posing substantial environmental issues.

In addition, the proliferation of medium-sized fish processing facilities along the lakeshores leads to a substantial quantity of waste. The Kenya Marine and Fisheries Study Institute (KMFRI) reports that 150,000 tons of fish waste are generated every year, of which 80% is dumped.

A substantial portion of the fish waste is swept into the lake, even though some of it ends up in open landfills. But now, a group of young scientists is attempting to resolve the trouble, turning fish waste into useful fish oil. Their efforts are element of a expanding trend in recycling Lake Victoria’s waste and turning it into usable goods.

Environmentalists have warned of the dangers in fish waste: When it decomposes, it consumes oxygen from the water. This can lead to oxygen depletion, which can harm fish and other aquatic organisms that need oxygen to survive.

In addition, excess amounts of fish waste and other nutrient sources can bring about eutrophication, which is when an excess of nutrients in the water leads to algal blooms and decreased water clarity. Fish waste can also include bacteria and viruses that can harm human well being if the water is applied for swimming, fishing or other recreational activities.

On the shores of Lake Victoria, quite a few varieties of fish, which includes the Nile perch, are processed for consumption and distribution. Image by Worldwide Atmosphere Facility by way of Flickr (CC BY-NC-SA two.).

Earnings possible in fish waste

Quite a few fishmongers are unaware that they are discarding possible sources of revenue by tossing out fish scales, bones, skins and bladders, which could be worth millions of shillings on regional and international markets, according to officials at the Kenya Fisheries Division.

According to study published in the International Journal of Environmental Study and Public Wellness and other journals, there are a lot of techniques to use fish waste to produce revenue based on regional industry demand, availability of sources and the technical know-how of the person or neighborhood involved.

For instance, fish waste can be applied to make higher-good quality organic fertilizer. Throughout the composting method, the organic matter in the fish waste breaks down, releasing nutrients that are critical to plant development. This organic fertilizer can be sold to farmers, landscapers and gardeners.

In addition, fish waste can also be processed into fish meal, which is a higher-protein feed ingredient applied in aquaculture and livestock feed. It can also be applied in aquaponics as a fertilizer for plants that purify the water it can be produced into biogas, a renewable power supply that generates electrical energy or heat by means of anaerobic digestion and the collagen located in fish waste can be applied in the production of cosmetics and healthcare items.

On Lake Victoria, regional communities are also discovering that fish waste can be converted into oil by means of a method referred to as rendering, which entails heating the waste to break down fats and oils. Afterward, the oil can be applied to make biodiesel, omega-three supplements and cosmetics. This production approach has reduced fees and a decreased environmental effect compared with classic fish oil production.

Preparation of fish waste.There are a lot of techniques to use fish waste to produce revenue based on regional industry demand, availability of sources and the technical know-how of the person or neighborhood involved. Photo courtesy of Dennis Otieno.

Regardless of obtaining a decade of expertise in the fishing business, Lucy Akinyi a Lake Victoria fishmonger, stated she is ignorant of the notion of omega-three fatty acids, generally recognized as fish oil, getting developed from the wastes she discards.

Alice Aluoch, yet another fishmonger, revealed that she sells only the fish meat and removes the scales with a knife, resulting in up to a 20-liter bucket of waste she discards every day.

At a fish industry with hundreds of fishmongers, this final results in tons of waste getting discarded every day.

More than the years, professionals have grappled with how to dispose of the matter. This is in order to save the lake, which is currently choked with pollution posing a threat to humans and aquatic life. According to the United Nations Atmosphere System, Lake Victoria faces a variety of types of pollution, which includes agricultural, which final results in damaging algal blooms by means of eutrophication.

The lake also suffers from industrial pollution such as heavy metals, chemical substances and other toxic substances. Higher levels of waste from human settlements, which includes sewage and strong waste, lead to the spread of waterborne ailments and invasive species such as water hyacinth. Along with invasive Nile perch, these species have left substantial ecological impacts on the lake, which includes the displacement of native species and modifications to the lake’s meals net.

A man wades through hyacinth growth on Dunga beach.A man wades by means of hyacinth development on Dunga Beach. Image by Marcel Crozet / ILO by way of Flickr (CC BY-NC-ND two.).

Science interns discover to extract oil from waste

In a surprising turn of events, Lake Victoria’s fish leftovers have proved to be a fortunate discover for a group of interns at KMFRI.

Dennis Otieno, an aquatic science graduate from Kenya’s Egerton University, has led a group of 5 interns who have developed revolutionary technologies capable of transforming fish waste into fish oil.

Fish oil, a wealthy supply of omega-three fatty acids, is discovering its way into a variety of items across a variety of industries. It is a well-liked dietary supplement for its positive aspects in advertising heart well being, brain function and minimizing inflammation.

In addition, fish oil is applied as a supplement in animal feed to boost livestock well being and the nutritional good quality of animal items. Industries such as paint, varnish and lubricant production use fish oil for its chemical properties.

Fish oil is also applied in the production of cosmetics, such as skin creams and lotions, due to its moisturizing and anti-inflammatory properties. And it is applied in pharmaceutical items to treat higher cholesterol levels.

Beyond fish oil, the interns have also created a approach of repurposing fish scales into attractive flowers for decorations in events and universities locally. Even though this remedy is at the moment getting implemented on a modest scale, it has the possible to be scaled up making use of sophisticated technologies to address the environmental challenge posed by fish waste.

The system was inspired by Otieno’s undergraduate project in 2017. Beneath the guidance of his supervisors, he extracted oil from the frequent carp (Cyprinus carpio) located in Lake Naivasha, northwest of Nairobi. Upon effectively finishing the project, he graduated and joined the Kenya Fisheries Division in Kisumu as an intern. Even though operating there, Otieno decided to collaborate with his colleagues to implement the project on the shores of Lake Victoria. And now, the group makes use of Nile perch waste to extract fish oils.

“If the project is upscaled, it can contribute to the improvement of atmosphere, increase well being of the folks, enhance revenue and boost livelihoods,” he stated.

Otieno stated he sees this as a remedy that could bridge the gap in the fishery worth chain and market environmental conservation.

Dennis Otieno giving a presentation about fish waste products at a summit.Dennis Otieno providing a presentation about fish waste items. Photo courtesy of Dennis Otieno.

With a locally produced oil extractor machine that fees $556, Otieno and his colleagues extract omega-three fish oils from Nile perch offal. This machine includes 3 most important elements that can also assess the good quality of a solution.

“The offal is fed into the machine, exactly where it is mixed with water and stirred at a extremely higher speed for a handful of minutes just before the final solution is developed,” Otieno explained.

The remains right after the oil extraction method are applied as chicken feed, gelatin and collagen applied to treat burns.

The extraction strategy follows common process as outlined in a 2019 study published in the journal Foods.

The study assessed the effect of a fish oil refining method in 4 stages: “degumming (to separate phospholipids), neutralizing (to decrease acidity), bleaching (to get rid of coloured components) and deodorization (to get rid of undesirable odour compounds).”

Otieno stated that considering the fact that they initiated the method in 2022, they have observed a rise in the regional community’s demand for fish oil. Therefore, regional purchasers acquire the oil straight from the production internet site.

“The accomplishment of the project has supplied financial empowerment for us, and our ultimate target is to turn into the major producer of omega-three fish oil, animal feed, gelatin and fish flowers in the area.”

According to him, if a fish weighing 18kg (40 pounds) is sold for $57, he can extract 11 liters (about three gallons) of oil from its waste and sell the oil for $65.

Regardless of this, Otieno stated the group is facing the challenge of inadequate funding, which has impeded their efforts to scale up production.

A fish oil extractor machine.With a locally produced fish oil extractor machine, Otieno and his colleagues extract omega-three fish oils from Nile perch offal. Photo courtesy of Dennis Otieno.

Expanding international markets for fish oil

According to a industry evaluation report by the company consulting firm Grand View Study, the international fish oil industry was valued at $two.25 billion in 2014. Newer forecasting by Vantage Marketplace Study showed anticipated development to attain $17 billion by 2028.

Financial study has shown that the demand for fish oil would most likely surge additional due to expanding awareness amongst customers of the well being positive aspects linked with omega-three consumption.

Moreover, the Grand View report predicted the business would expertise an enhance in demand due to shifts in dietary habits that outcome in higher consumption of hydrogenated vegetable oils and margarine. In addition, the use of fish oil in protective coatings and lubricants was anticipated to be a driving aspect in business development.

Mongabay spoke to William Okello, one particular of the prospects who acquire oil from Otieno and his group, who stated his well being enhanced right after consuming a teaspoon of the oil. One more client, Ann Akinyi, who was six months pregnant, reported that the oil from Otieno prevented her feet from swelling, a frequent challenge amongst pregnant girls.

Study has shown that fish oil can have possible positive aspects in addressing pregnancy-associated challenges. According to a study published in the journal Critiques in Obstetrics and Gynecology, taking fish oil supplements throughout pregnancy may perhaps support to decrease the threat of preterm birth, low birth weight, and preeclampsia.

“I take a spoonful of the oil right after I cook vegetables and sprinkle the oil more than them just before consuming,” Akinyi stated.

In order to achieve a lot more well being positive aspects from omega-three fatty acids located in fish, the Globe Wellness Organization (WHO) recommends consuming 1-two servings of fish per week, as this may perhaps provide protection against a variety of ailments.

Further positive aspects of fish oil contain advertising heart well being, aiding in the therapy of some mental well being circumstances, supporting eye well being, minimizing inflammation, enhancing skin well being, minimizing liver fat and alleviating symptoms of depression.

Locals sample fish oil products.Locals sample fish oil items. Photo courtesy of Dennis Otieno.

From fish scales to flowers

Apart from fish oil extraction, Otieno identified the environmental impacts of fish waste and set out to learn other inventive options to the challenge.

“I was inspired by the attractive arrangement of fish scales and believed that they could be transformed into beautiful flowers,” Otieno explained, noting that he could generate up to 5 bouquets in a single day.

The method of fashioning flowers from fish scales entails initial washing them and then soaking them in dye derived from plant pigments just before air-drying them for a minimum of 3 hours.

Otieno then joins with each other the colorful scales making use of a fish skin-derived adhesive to generate a variety of styles and patterns.

He sells them to the regional neighborhood and, at occasions, for weddings and anniversaries.

Otieno has showcased this innovation in distinctive conferences such as the United Nations Atmosphere Assembly (UNEA-five.two) held in Nairobi in February and March 2022 to market the flowers’ sale to the public. He stated he believed capital investment in aquaculture was important.

Chrispin Nyamweya, assistant director and study scientist at KMFRI, praised the innovations by the interns and revealed that there are plans to certify the items for significant-scale production.

He pointed out that KMFRI intended to seek the approval of agencies, which includes the Kenya Bureau of Requirements, to guarantee meals security for each flowers and fish oil just before the technologies would be provided to industries to implement.

Nyamweya additional stated that KMFRI is taking time with the method to patent the technologies and safe copyright for the young innovators.

A bouquet of flowers made with fish scales.A bouquet of flowers produced with fish scales. Photo courtesy of Dennis Otieno.

Fish waste recycling expanding on Lake Victoria

Fish waste recycling has gained traction in the current previous amongst distinctive groups in Kenya. For instance, girls on the shores of Lake Victoria collect freshly discarded fish waste, which consists of skin and bones left right after filleting. Following smoking and drying the waste, they grind it with a milling machine.

Isabella Asamba, an environmentalist at Maseno University, explained that the animal feed developed from fish waste is nutritious and can improve the productivity and well being of piglets, calves and chicks.

The skin from bigger Nile perch is delivered to the Kenya Industrial Study and Improvement Institute to be treated and tanned into sturdy leather that is much less prone to decomposition. Prior to sun-drying, chemical substances are applied to eradicate the fish oil from the skin, and table salt is added.

According to Asamba, the leather is then applied to generate footwear and handbags. This implies that “we have found a a lot more appropriate and lucrative method to using fish waste rather than discarding it,” Asamba stated. Raw components are readily offered, as Nile perch accounts for 70% of Lake Victoria’s total fish catch.

Nyamweya observed that fish waste recycling has had a good effect on the atmosphere on the shores of Lake Victoria. “Previously, the fish waste would be left to rot on the shorelines, causing pollution and making a foul smell. Even so, with the introduction of fish waste recycling, the waste is now getting utilized to generate useful items such as fish oil and animal feed,” he stated.

He explained that this has not only decreased pollution but also supplied a supply of revenue for regional communities. Moreover, the recycling method has helped to boost the hygiene and sanitation of the regional region. General, he stated, the recycling of fish waste has had a substantial good effect on the atmosphere, economy and neighborhood well being on the shores of Lake Victoria.

Banner image: Fishers going fishing at Dunga Beach, Kisumu. Image by Marcel Crozet / ILO by way of Flickr (CC BY-NC-ND two.).

Boom and bust on Lake Victoria: Q&ampA with author Mark Weston


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Coletta, J. M., Bell, S. J., &amp Roman, A. S. (2010). Omega-three Fatty Acids and Pregnancy. Critiques in Obstetrics and Gynecology. Retrieved from

Neighborhood Improvement, Neighborhood-primarily based Conservation, Conservation, Atmosphere, Fish, Fishing, Meals, Meals Sector, Meals Waste, Freshwater Fish, Lakes, Pollution, Waste, Water Pollution

By Editor