Researchers in the Netherlands have come up with a new, more sustainable way to feed salmon that are grown in aquaculture environments: insects.
Most of the salmon that consumers eat is raised in pens, where they are fed a specific diet that helps them grow. In the past, much of that diet has been based on fish meal, a protein and nutrient-rich mixture made from fish that were caught expressly for the purpose of feeding them to other fish.
That practice has drawn criticism from conservationists, however, who point out that it’s an inefficient process that contributes to overfishing and the bycatch of sensitive marine organisms like whales and sea turtles.
Seeking an alternative, the Netherlands-based company Protix developed a fish meal that’s based on insects. Researchers came up with the idea for the insect-based feed when they noticed animals like chickens, when they’re young, eating insect larvae to gain protein.
“Salmon are one of the more demanding fish species to grow,” says Tarique Arsiwalla, chief commercial officer of Protix. Right now, in order to create fish meal for salmon to eat, much of the aquaculture industry is “catching fish we don’t like to eat to create the salmon that we want,” he notes.
Starting in 2014, teams at Protix researched different types of insects. Eventually, they discovered that the black soldier fly has a large amount of protein stored during its larvae stage because the fly doesn’t eat once it is hatched.
Salmon, which are notoriously picky, liked the food made from the black soldier flies better than the other alternatives.
Because salmon can take up to two and a half years to mature, and because most new types of feed are only tested for a couple of months, there is often reluctance in the aquaculture industry to try new kinds of feed, says Aarts. In an attempt to attract interest, Protix tested the new insect-based food for four years.
“We come from an age where we thought the big blue ocean was infinite,” says Kees Aarts, Chief Executive Officer of Protix. “But with increasing demand for production of salmon, we need that alternative.”
As recently as a few years ago, it took the equivalent of three fish ground up into meal to make enough food to sustain one farm-raised salmon. That’s not an efficient use of the world’s resources, environmentalists like Oceanaand WWF said. At the same time, demand for salmon around the world has been soaring. In response, the industry worked hard and eventually got the ratio down to one and a half fish for every salmon produced (largely by adding plant-based foods like corn and soy to the mix). But that ratio still requires fishing.
The fish used to make the fish-based meal can contain traces of chemical runoff from soil, plastics that the animals may have encountered in the ocean, and other toxins (like mercury from power plant emissions). Those compounds can get ingested by salmon and eventually land on the dinner plate of the people who buy them.
Tim Cashion, a University of British Columbia Ph.D. student in the Fisheries Economics Research Unit of the Institute for the Oceans and Fisheries, says the industry has already reduced the amount of fish meal used in the process substantially, from 100 percent in the 1960s and ‘70s down to about 30 percent when he last published a study on it in Norway in 2012. However, those sources don’t necessarily replace all of the amino acids that salmon need, and they don’t replace the fish oils that make salmon so healthy to eat.
“The oil might be the part that’s harder to replace,” Cashion says. “It’s about getting the kinds of fats that people want in their salmon. That’s why you can’t do a complete replacement of fish oil with other kinds of oils.”
While the insect-based feed only replaces the proteins that salmon eat, Aarts says alternatives for the fish oils, which are currently still sourced from ocean life, are also in development by companies like DSM and Evonik.
A major concern that companies like Protix are facing is the scale that’s needed for insect-based feed to be successful in the aquaculture industry.
“The current demand for fish meal is approximately 6 million tons per year,” Cashion says. “[If] the idea is to replace that 100 percent with insect feed or insect meal of various kinds, we need a lot of it. The current production as I understand it is not there, but this is obviously a fairly new kind of industry.”
He wonders if it is feasible to meet that kind of demand in a timely fashion, and says its success also depends on the price of the insect-based feed.
“If they can buy insect meal for cheaper than fish meal and they can get the same results, they will likely do it, if it can work at the scale they’re producing at,” he says.
Because it is still a new product, Aarts says the insect-based meal is still slightly more expensive than fish meal, but fish meal prices are expected to rise as the amount of fish in the ocean decreases and demand for salmon continues to increase. As Protix expands to address the amount of feed that is needed, Aarts expects scale factors to drive the cost of the feed down as well.
The flavor of the salmon that ends up on consumers’ plates isn’t impacted by insect-based feed, either, says Arsiwalla. “The best result we could get was that it tastes like a salmon should taste, even though we made a significant change in the feed,” he says. “A salmon should taste like a salmon.”
To prove it, the company had their salmon taste-tested in blind judging. No one could tell the difference between their salmon and the salmon raised on conventional feed.
Protix is now working on scaling up their production, which is based in the Netherlands but has new projects across Europe, Asia, and Mexico. They are working on using food waste from vegetables produced by other food companies to feed the fly larvae, which they grow in their own facility. They will be opening a second facility soon, and together with other companies that make insect-based feed, they successfully lobbied the European Union for approval to sell their products in countries that are a part of the union as of July 2017.
“We believe the industry is set to grow fast,” Aarts says. “Our aim is to show safety, economic, and environmental potential of this new category of ingredients, from which new releases can be developed, like the inclusion in chicken feed.”
After the EU’s approval, Aarts says there was a fast increase in demand for insect-based feed. Protix is interested in working on feed for other aquaculture species as well, like trout and shrimp.
“We have to take care of our planet, and we believe that all people need to have access to proper nutrition in all phases of life,” says Aarts. “That also means [proper nutrition] for the animals we grow to feed ourselves.”