Nourishing the world with sustainably farmed salmon
Over half of all the fish that people eat comes from aquaculture, the farming of aquatic species. Modern aquaculture, which started with salmon farming about five decades ago, has become the fastest growing sector of food production in the world. Compared to other agricultural sectors, aquaculture is relatively new, but it is already playing a significant role in providing a healthy and nutritious protein source for billions of people worldwide.
Amid this rapid growth, the aquaculture industry has been making strides to reduce its environmental impact. Advancements in science and technology, along with the adoption of new management practices, are propelling fish farming into a more sustainable future.
Farmed fish’s positive impact on food security and human nutrition
Along the southwest border of the Netherlands, Alltech Coppens Aqua Centre is working to make sustainable fish farming practical and measurable. Ben Lamberigts is leading the quality, research and nutrition teams at the global producer of fish feed.
“If you look at all the things we can quantify from aquaculture, like feed conversion, use of raw materials, water use and efficiency, then aquaculture is the number one production system for feeding protein to the world in the future if we grow to 10 billion people,” said Lamberigts.
“It’s possible to stay healthy as a vegetarian, but then you need a certain form of nutrition that is very diverse, and that is not possible in all countries,” he continued. “The protein that we want to provide for human nutrition via livestock production, including aquaculture — that is mainly for a healthy and diverse protein diet.”
In addition to providing a crucial protein source, fish play an important role in delivering the fatty acids that humans need, such as EPA, DHA and omega-3. These fatty acids support brain function and lower the risk for heart diseases.
“Of course, you can eat algae, but fish and crustaceans (shrimp, crab and lobster) are the common sources from which humans can get fatty acids,” Lamberigts explained.
To provide humans with optimal nutritional benefit, the fish need to get a sufficient level of protein and fat from their feed. Aquafeed formulation considers nutrition, sustainability and cost factors.
The rise of sustainable fish feed
As with most protein sectors, fish feed represents the largest cost to producers while also playing a significant role in animal health, human nutrition and environmental sustainability.
Traditionally, fishmeal and fish oil made from wild-caught fish were the primary sources of protein and fat in fish feed for aquaculture. However, these raw materials will not be enough for fish feed production to meet demand in 2050 if the current feed formulation stays the same
Over the past 15 years, fish nutritionists have successfully reduced fishmeal and fish oil content in feed formulation by using different primary sources for protein and fat, such as land animal byproducts (hemoglobin, blood meal, poultry meal) and plants. This is possible because fish need the nutrients from the raw materials, not the raw materials themselves.
Here is the breakdown of an aquafeed formula by Alltech Coppens that significantly reduces the content of marine resources:
“It’s possible to reach carbon neutrality within a practical aquaculture diet, but that journey starts from understanding what we can measure in terms of sustainability within the raw materials that we use,” said Philip Lyons, global manager of aquaculture research at Alltech Coppens.
Sustainable fish production driven by research and technological development
Quantifying sustainability and optimizing feed efficiency has proven achievable by:
1. Ensuring feed efficiency through precise formulation
Choosing raw materials that are good for the fish and the environment starts with understanding the digestibility of different feed ingredients for different fish species.
All animal feeds contain a certain amount of energy, which is mainly derived from protein, fat and carbohydrates. This dietary energy is a common predictor for growth in feed formulation. In reality, some of this energy is not digested and is therefore not available to the fish. Of what the fish can digest, known as digestible energy, a part is lost as the result of metabolism. The energy that is left for maintenance and growth of the fish is called net energy.
“Currently, aqua feeds are commonly formulated on a digestible energy basis,” said Lyons. “That assumes the macronutrients within the diet — protein, fats and carbohydrate — are all utilized in the same way. But the next step is net energy, because it assumes that the utilization efficiencies for growth of that protein, fat and carbohydrate are different.”
Alltech Coppens studied the growth of different fish species to tailor feed formulation based on the net energy they will receive after digesting the feed. This enables more precise formulation in aquafeeds, which is important because it allows more flexibility in selecting raw materials for the feed while assuring consistent performance for the farmer. By knowing the net energy content of the feed, farmers are able to predict the growth performance they will get from that feed and not waste nutrients.
When it comes to an offshore cage farm, feed efficiency matters, because if the fish does not digest the feed well, nutrients will be lost to the environment. The excess nutrients from wasted feed can trigger an algal bloom, which can use up the oxygen and choke the fish. In other words, what the fish doesn’t properly digest could end up killing it.
“Formulating feeds precisely so that you lower that nutrient loss to the environment is everything when it comes to sustainability,” said Lyons, “because you’re not only harming the farming system if it’s offshore, you’re also harming the farming environment. That’s essentially why it really matters to measure these things with detail so that we can be as efficient as possible in the (feed) technologies that we’re producing.”
2. Measuring all sustainability aspects in feed
Alltech Coppens has successfully lowered its “fish in fish out” ratio — also known as FIFO factor — to a more optimal level than the global industry standard. FIFO measures the number of wild-caught fish required in feed to produce 1 kilogram of farmed fish. The industry standard is 0.27, meaning 270 grams of wild-caught fish is needed to produce 1 kilogram of farmed fish. Alltech Coppens’ feed only uses 100 grams of wild-caught fish to produce the same result. Moreover, the marine raw materials it uses come from certified trimmings, the byproduct of wild-caught fish that is not consumed by humans and is often discarded, but which still contains valuable nutrition.
The company did not stop at this achievement. Currently, Alltech Coppens quantifies sustainability in a broader way.
“Sustainability means that we quantify all the measurables involved with the impact our industry has on the planet,” said Lamberigts.
He explained that measuring sustainability has two parts: The raw materials that are bought and what is done with them. This includes producing feed, transporting feed to customers and carrying out research. Lamberigts estimates that the first part, raw materials, accounts for 85% of the environmental impact.
In line with its commitment to United Nations Sustainable Development Goal 14 (Life Below Water) and to reduce its dependency on marine ingredients, Alltech Coppens has developed a sustainability scoring index for its feeds. The score-ranking system is established by a life cycle assessment (LCA). LCA comprises all phases needed to produce and use a product, from initial development to waste treatment.
“I think sustainability is much more than carbon footprints,” said Maud Valkenaars, nutritional researcher at Alltech Coppens. “We should take into account the land use, water use, acidification and toxicity for human health (impact) when scoring aquafeeds.”
By measuring the sustainability metrics within fish feed, Alltech Coppens can show the data that explains how sustainable each raw material is and formulate diets based on its sustainability score. Then, the farmer can choose which diet they want to use while knowing exactly how sustainable it is and how it affects fish health as well as consumer health.
Sustainable salmon farming reflected in the waters of Chile
Chilean Patagonia is breathtakingly gorgeous with its high mountain peaks, an abundance of glaciers, pristine waters and an array of wildlife. In the past 35 years, it has become a hub for salmon farming, maintaining a 5-6% growth rate each year over the last decade. Today, Chile is the world’s second-largest producer of farmed salmon.
Arturo Clément is credited with bringing salmon farming to Chile and serves as the president of SalmonChile, a national industry body created to address the challenges facing salmon farming. Clément says that part of the rapid growth of the Chilean salmon industry is not due to producing more fish, but through improved production indicators, which have been strengthened by better regulation, innovative processes and sustainable practices. Sustainability, says Clément, is key.
“We need to work much more in sustainability,” he said. “That is the main goal for the industry.”
Twenty-three companies in the SalmonChile group entered a clean production agreement to measure their carbon, water and energy footprint, as well as to mitigate greenhouse gas emissions. Their shared goal is to be carbon neutral by 2030.
Among these companies is Ventisqueros, Chile. Ventisqueros produces 4,500 tons of salmon every year. Their process provides insights into the management practices that are creating a more sustainable fish farm.
Stage 1: Hatchery inland
Sustainable land use: In a room the size of a fancy walk-in closet, 2 million salmon eggs resembling tiny orange balls are stored. When the eggs hatch, the young fish swim in an indoor tank for three months. After that, they move outdoors to larger fresh-water tanks.
Sustainable water use: The water in those tanks comes directly from a glacier — the same glacier that created Chile’s striking scenery millions of years ago.
Stage 2: Moving to the ocean
Sustainable feeding: A year later, nearly a million fish move from the land-based tanks to the ocean in offshore cages. To minimize the impact on the seabed from feed waste, each fish is monitored on camera from a feeding center 200 kilometers away. It uses artificial intelligence (AI) in aquaculture to stop feeding the fish as soon as they appear full. This minimizes feed waste and prevents polluting the sea.
Sustainable feed: Ventisqueros has a sustainable salmon product called Silverside™, fed with a diet that contains mostly algae and only a small portion of animal protein. Traditionally, salmon eat smaller fish, which eat zooplanktons, which eat algae in the ocean. Algae delivers a high source of omega-3 for the fish that eat them. By feeding algae directly to the salmon, Ventisqueros reduces the amount of little fish pulled from the ocean while still maintaining a high omega-3 diet for the farmed fish. This provides healthy food to people while lowering marine dependency.
Stage 3: From farm to food
Ten months after being in the ocean, the fish move to the processing plant. It only takes 15 minutes to fillet the fish after they arrive. What happens after is even more impressive:
Zero waste: All of the fish gets used, even the scraps. The parts that won’t get eaten are used as raw materials for fish feed, fish oil, pet food and omega-3 capsules.
Sustainable packaging: The materials used are 100% recyclable and biodegradable.
“The idea is that by the end of 2026, we will be able to reduce to 0% the amount of waste sent to the landfill,” said Igor Stack, technical manager of Ventisqueros, who is proud of the work he does at the company, where he can contribute not only to salmon farming, but also to the planet.
The future of fish
The world’s demand for fish, a crucial source of protein and healthy fatty acids for humans, will continue to increase. So will the demand for sustainable fish production. From feed formulation to farming to food production, the aquaculture sector has made strides in every area to support fish, human health and the environment.
Nutritionists are formulating aquafeeds to optimize feed efficiency, reduce marine dependency, protect the ocean from feed waste and ensure a high level of nutrition for human health. Fish farmers are using advanced technology such as AI to monitor feeding in sea cages to avoid polluting the seabed while making uses of all parts of the fish and packaging them sustainably. Companies are quantifying sustainability metrics and helping each other to be more sustainable.
“We have to remember that aquaculture is still a relatively young industry…that’s what makes it exciting,” said Lyons. “(We are) constantly on the cusp of new technologies and new discoveries. I think we’ve only scratched the surface when it comes to aquaculture and the potential that it has within the food production system.”
Author: Tien Le | July 5, 2022