Millions of larvae breed as an alternative fish and animal feed

Earth seems to move in a long corridor of ‘insect factory’ Protix. In green bins, brown, dry grit gently ripples up and down. Elselina Battenberg, spokesperson for Protix, slides her fingers through the grit in blue plastic gloves. Just below the earthy surface in the crate, hundreds of larvae become visible crawling about. In her palm she scoops up a few larvae. “They’re a little warm.”

Insect factory Protix breeds millions of insects for animal and fish feed. Earlier this year, the factory entered into a partnership with Albert Heijn, among others, for making feed for growers who sell to the supermarket. Farmed fish and crustaceans are often fed with caught fish, which means that farmed fish contributes to overfishing. Protix produces animal proteins without this leading to a lot of land consumption, as an alternative to soy cultivation, or overfishing.

“When the grit is dry and rippling, they’re done eating,” says Battenberg. Mechanical green crates, each containing hundreds of teeming larvae, glide along a conveyor belt through a large hall. They are tipped over into other bins with a wet, beige mush. It is the food for the animals, consisting of residual flows from the food industry, such as green waste from beer brewers and potato processors. These residual flows are usually used for biomass plants, for example, or they are thrown away.

Further into the factory, a black, thin fly lands on the reporter’s notebook. “They are very calm,” says Battenberg, “you can catch him in no time.” The creature is called the black soldier fly. It is the only strain in the factory and is grown by the millions at a time. The fly does not occur in the Netherlands (too cold), but it does occur in North and South America.

The breeding and processing process of the flies, “from egg to protein”, takes about fourteen days. The larvae are fed every two days. Some of the larvae leave the nursery alive, as chicken feed. The bulk is further processed into protein powder, fat or puree, which is feed for fish, piglets, dogs, cats and shrimps. What remains (skins and faeces) is sold as an alternative to fertilizer for tomato and strawberry plants, for example.

Photos Olivier Middendorp

Competitive alternative

Entrepreneurs Kees Aarts and Tarique Arsiwalla founded Protix in 2009. The aim was to offer a sustainable and competitive alternative to fish and livestock feed with the mass production of insects. It was difficult for the company to establish a position between soybean and fishmeal suppliers.

“We had to convince our customers that it works,” says Battenberg, “and they, in turn, had to test it in animals.” Protix also had to wait for legislation. For a long time, pigs and chickens were not allowed to receive animal proteins. That has changed in 2021.

The company received a capital injection of 45 million euros in 2017, including from Rabobank and investment company Aqua-spark, and was able to build a factory in Bergen op Zoom. It has been operational since 2019. The location is huge for an insect factory: 15,000 square meters. Seven days a week, 24 hours a day, millions of insects are cultivated simultaneously. In 2022, Protix had a turnover of around 9.5 million euros. Nearly two hundred people work there.

Soon shrimps that are in the Albert Heijn will also eat Protix feed. The first loads of feed with ingredients from Protix have arrived in Ecuador at the shrimp farmer who supplies Albert Heijn. For this, the shrimp ate a mix of fish meal and soy. Protix also supplies feed manufacturers for salmon and trout farmers, although this is still in a pilot phase.

Originally farmed fish ate a lot of caught fish. “But in recent decades, the farmed fish industry has grown so fast that the sea was not big enough,” says Michel van Spankeren, business development manager at Protix. “Then the soy industry jumped into that gap.”

Protix points out that large-scale soy cultivation leads to deforestation. This also applies to palm oil, another important source of nutrition in animal feed. “Moreover, salmon are carnivores by nature, and therefore benefit better from animal than vegetable proteins,” says Van Spankeren.

There is a strong smell of ammonia in the factory, especially in the ‘climate cells’, of which Protix has six. In each of the cells there are more than 5,700 crates filled with larvae crawling around in their food. Behind a heavy door, in a warm cell, the air stings your eyes. This is where the larvae reside when not being fed. “The food has just been refilled, then the smell is the strongest,” says Battenberg.

Nitrogen emissions

Ammonia is a compound between hydrogen and nitrogen, the gas that is politically speaking hot topic is because too much of it is emitted. The factory also has nitrogen emissions, says Battenberg, “from truck traffic, and from the biological process of insect breeding.” To reduce these emissions, Protix uses a technical system that extracts and scrubs the air to remove bound nitrogen from the air. “The advantage,” says Battenburg, “is that the factory is closed off from the outside air, in contrast to open cowsheds.” The factory would first be built right next to a residential area in Den Bosch. After concerns of local residents about an ammonia smell and freight traffic, Protix moved to the industrial estate in Bergen op Zoom.

The footprint of larvae as a protein source is low, but the factory does use energy

The extent to which larvae are a sustainable source of protein depends on what you compare it to, and what criteria you look at, a study showed. analysis of the German Institute for Food Technology. The footprint in terms of CO2 and other greenhouse gases is 24 times lower for a kilo of larva puree than for a kilo of chicken meat, which is also used for pet food. If you compare a kilo of insect meal with a kilo of soybean meal, the greenhouse gas footprint is seven times lower.

But sustainability is about more than greenhouse gases. If you look at the required amount of land and fresh water, insects also score better than soy. In some cases, soy and fish require less energy than an insect factory. The electricity from the Protix production location in Bergen op Zoom does come entirely from the sun and wind.

‘Quasi-green development’

From the angle of animal rights there is criticism of intensive insect farming. For example, lobby organization Eurogroup for Animals wrote in 2021 that there is too little knowledge about the welfare of insects. There is some evidence that insects can also experience pain.

In 2019, following the opening of the nursery in Bergen op Zoom, Esther Ouwehand of the Party for the Animals spoke of a “quasi-green development”. “We are now going to set up an entire industry to maintain the factory farming industry,” she told NOS at the time.

“Intensive farming suits insects better than other animals,” says Battenberg. “They also naturally huddle close together. That is their survival mechanism. Unlike mammals, they don’t have that need for space.” The larvae are slaughtered, says Battenberg, by washing them with cold water. “That makes them drowsy, and then they quickly grind.”

Eurogroup for Animals also warned of disease spread. Intensive fly farming would entail similar risks of disease development as other forms of intensive animal husbandry. According to Protix, this is different. “We keep a close eye on the science,” says Battenberg. “As far as is known, no disease has yet been found in the black soldier fly. The animal has a good immune system and is hygienic. As a flying adult, he doesn’t even eat anymore. The only function it then has is to reproduce.”

“Look,” she says, pointing to the head of the fly. “He doesn’t even really have a mouth. Just a kind of sponge for water. He lives for about a week and then dies.”

The factory full of treadmills, on which the crates with insects slide at high speed, is intended to give nature a helping hand. But nature itself is hard to find in the huge industrial halls. Still, says Battenberg, “it has to be on such a large scale. Otherwise you have no impact on a sector.”

Nature is an inspiration for the factory, she says. “Nothing is left over, everything is used. We use residual flows from the food industry as food, the larvae for proteins and fats, and we also use the faeces and skins as natural fertilizer.”