The larvae of adult black soldier flies can turn food waste into sustainable protein with minimal methane gas emissions.
In Sydney, Australia, in the basement of an inner-city high-rise, lives a mass of unexpected inhabitants: millions of maggots. The insects are far from unwelcome. They are there to feast on the food waste generated by the building's human residents.
Goterra, the start-up that installed the maggots in the building in December, belongs to the rapidly expanding insect agriculture industry, which is experiencing a surge of investment worldwide.
The maggots – the larvae of the black soldier fly – are voracious, unfussy eaters. As adult flies, they don't eat, so the young fatten up swiftly on whatever they can get. Goterra's basement colony can munch through 5 metric tons of waste in a day.
"Maggots are nature's cleaners," says Bob Gordon, Head of Growth at Goterra. "They're a great tool to manage waste streams."
Their capacity to consume presents a neat response to the problem of food waste, which contributes up to 8% of global greenhouse gas emissions each year as it rots in landfill.
"The maggots eat the food fairly fresh," Gordon says. "So, there's minimal degradation and you don't get those methane emissions."
Alongside their ability to devour waste, the soldier fly larvae hold further agricultural promise: they yield an incredibly efficient protein. After the maggots have binged for about 12 days, Goterra harvests and processes them into a protein-rich livestock feed. Their excrement, known as frass, is also collected and turned into soil conditioner.
"We are producing protein in a basement," says Gordon. "It's urban farming – really sustainable, urban farming."
Goterra's module in the basement at Barangaroo, Sydney.
Supplied by Goterra
Goterra's founder Olympia Yarger started producing the insects in "buckets in her backyard" in 2016. Today, Goterra has a large-scale processing plant and has developed proprietary modules – in shipping containers – that use robotics to manage the larvae.
The modules have been installed on site at municipal buildings, hospitals, supermarkets, several McDonald's restaurants, and a range of smaller enterprises in Australia. Users pay a subscription fee and simply pour in the waste; Goterra visits once a fortnight to harvest the bugs.
Insect agriculture is well established outside of the West, and the practice is gaining traction around the world. China has mega-facilities that can process hundreds of tons of waste in a day. In Kenya, a program recently trained 2000 farmers in soldier fly farming to boost their economic security. French biotech company InnovaFeed, in partnership with US agricultural heavyweight ADM, plans to build "the world's largest insect protein facility" in Illinois this year.
"The [maggots] are science fiction on earth. Watching them work is awe-inspiring."
But the concept is still not to everyone's taste.
"This is still a topic that I say is a bit like black liquorice – people tend to either really like it or really don't," says Wendy Lu McGill, Communications Director at the North American Coalition of Insect Agriculture (NACIA).
Formed in 2016, NACIA now has over 100 members – including researchers and commercial producers of black soldier flies, meal worms and crickets.
McGill says there have been a few iterations of insect agriculture in the US – beginning with worms produced for bait after World War II then shifting to food for exotic pets. The current focus – "insects as food and feed" – took root about a decade ago, with the establishment of the first commercial farms for this purpose.
"We're starting to see more expansion in the U.S. and a lot of the larger investments have been for black soldier fly producers," McGill says. "They tend to have larger facilities and the animal feed market they're looking at is potentially quite large."
InnovaFeed's Illinois facility is set to produce 60,000 metric tons of animal feed protein per year.
"They'll be trying to employ many different circular principles," McGill says of the project. "For example, the heat from the feed factory – the excess heat that would normally just be vented – will be used to heat the other side that's raising the black soldier fly."
Although commercial applications have started to flourish recently, scientific knowledge of the black soldier fly's potential has existed for decades.
Dr. Jeffery Tomberlin, an entomologist at Texas A&M University, has been studying the insect for over 20 years, contributing to key technologies used in the industry. He also founded Evo, a black soldier fly company in Texas, which feeds its larvae the waste from a local bakery and distillery.
"They are science fiction on earth," he says of the maggots. "Watching them work is awe-inspiring."
Tomberlin says fly farms can work effectively at different scales, and present possibilities for non-Western countries to shift towards "commodity independence."
"You don't have to have millions of dollars invested to be successful in producing this insect," he says. "[A farm] can be as simple as an open barn along the equator to a 30,000 square-foot indoor facility in the Netherlands."
As the world's population balloons, food insecurity is an increasing concern. By 2050, the UN predicts that to feed our projected population we will need to ramp up food production by at least 60%. Insect agriculture, which uses very little land and water compared to traditional livestock farming, could play a key role.
Insects may become more common human food, but the current commercial focus is animal feed. Aquaculture is a key market, with insects presenting an alternative to fish meal derived from over-exploited stocks. Insect meal is also increasingly popular in pet food, particularly in Europe.
While recent investment has been strong – NACIA says 2020 was the best year yet – reaching a scale that can match existing agricultural industries and providing a competitive price point are still hurdles for insect agriculture.
But COVID-19 has strengthened the argument for new agricultural approaches, such as the decentralized, indoor systems and circular principles employed by insect farms.
"This has given the world a preview – which no one wanted – of [future] supply chain disruptions," says McGill.
As the industry works to meet demand, Tomberlin predicts diversification and product innovation: "I think food science is going to play a big part in that. They can take an insect and create ice cream." (Dried soldier fly larvae "taste kind of like popcorn," if you were wondering.)
Tomberlin says the insects could even become an interplanetary protein source: "I do believe in that. I mean, if we're going to colonize other planets, we need to be sustainable."
But he issues a word of caution about the industry growing too big, too fast: "I think we as an industry need to be very careful of how we harness and apply [our knowledge]. The black soldier fly is considered the crown jewel today, but if it's mismanaged, it can be relegated back to a past."
Goterra's Gordon also warns against rushing into mass production: "If you're just replacing big intensive animal agriculture with big intensive animal agriculture with more efficient animals, then what's the change you're really effecting?"
But he expects the industry will continue its rise though the next decade, and Goterra – fuelled by recent $8 million Series A funding – plans to expand internationally this year.
"Within 10 years' time, I would like to see the vast majority of our unavoidable food waste being used to produce maggots to go into a protein application," Gordon says.
"There's no lack of demand. And there's no lack of food waste."
In this illustration of immune defense, Y-shaped proteins called antibodies attack a virus.
When we get sick, our immune system sends its soldier cells to the battlefield. Called B-cells, they "examine" the foreign particles that shouldn't be in our bloodstream—and start producing the antibodies, the proteins to neutralize the invaders.
To screen the antibodies, scientists have developed a proprietary way to make the effective ones glow – like a literal "lightbulb" moment.
The better these antibodies are at neutralizing the pathogen, the faster we recover.
The antibodies acquired from COVID-19 survivors already showed promise in treating other patients, but because they must be obtained from people, generating a regular supply is not feasible. To close the gap, researchers are trying to identify the B-cells that make the best antibodies—and then farm them in laboratories at scale.
Scientists at Berkley Lights, a biotechnology company in California, have been screening B-cells from recovered patients and testing the antibodies they release for virus-neutralizing abilities. To screen the antibodies, scientists there have developed a proprietary way to make the effective ones glow – like a literal "lightbulb" moment.
So how does it work? First, the individual B-cells are placed into microscopic chambers called nano-pens, where they secrete the antibodies. Once released, the antibodies are flushed over tiny beads that have bits of the viral particles attached to them, along with special molecules that can emit fluorescent light.
"When an antibody binds to the bead, we see a bright light on the bead," explains John Proctor, the company's senior vice president of antibody therapeutics. "So we can identify which cells are making the antibodies."
Then the antibodies are tested for their ability to counteract the coronavirus's spike proteins, which the virus uses to break into our cells. Not all antibodies are equally good at this crucial defense move—some can block only parts of the virus's machinery, while others can neutralize it completely. Proctor and his colleagues are looking for the latter.
Once scientists identify the best performing B-cells, they crack the cells open—or in scientific terms "lyse" them—and extract the genetic instructions for making the antibodies. As it turns out, B-cells aren't very efficient at pumping out massive amounts of antibodies, so scientists insert these genetic instructions into a different, more prolific type of cell.
Named Chinese Hamster Ovary Cells or CHO, these cells are commonly used in the pharmaceutical industry because they can generate therapeutic proteins en masse. Under the right nutrient conditions, which include a lot of sugar, CHO cells can keep making the antibodies at commercial levels. "They are engineered to operate in very large bioreactors," Proctor explains.
While traditional antibody screening can take three months, the Beacon System can do it in less than 24 hours.
Berkeley Lights' technology has already been used to screen the antibodies of recovered patients from Vanderbilt University Medical Center. In another example, a biotech company GenScript ProBio used the platform to screen mice engineered to have human antibodies for the coronavirus.
In addition to its small, lab-on-a-chip size, Berkeley Lights' system allows scientists to greatly speed up the screening process. While traditional antibody screening can take three months, the Beacon System can do it in less than 24 hours. "We only need one B-cell per pen and a couple of beads to see that fluorescent signal," Proctor says. "It is a more advanced way to process and analyze cells, and that level of sensitivity is unique to our technology."
B-cells secreting antibodies inside the Berkeley Lights Beacon System Nano-Pens.
While vaccines are likely to take months to develop and test, antibodies might arrive to the battleground sooner. With the extremely limited treatment options for COVID-19, antibody-based therapeutics can potentially bridge this gap.
