Got Food Waste? Get Some Maggots

In just a few hours, these tiny crawlers can eat more than their weight in food

Black soldier fly
Black soldier fly larvae Dennis Kress

Food waste is major global problem. According to the U.N.'s Food and Agriculture Organization, one third of the food produced each year, about 1.3 billion metric tons, spoils or is simply tossed out.

While composting can help compensate for some of that waste, most backyard compost systems aren't equipped to deal with all types of food and require proper tending to keep the decomposition churning along. Even then, it takes weeks to months for that food to turn to nutrient-rich fertilizer. But as Ludovic Ehret reports for Agence France-Presse, some farms in China are now recycling that food waste with a surprising little helper: maggots.

A farm in Sichaun Province, outside the city of Pengshan, relies on thousands of larvae from black soldier flies to chow down on their leftovers, Ehret reports. These maggots are especially efficient at converting protein into body mass, making them a good choice for processing waste food. About 2.5 pounds of maggots can munch through five pounds of food waste in about four hours.

Though the idea may be stomach churning, it makes ecological sense. The farm receives its food waste from a company called Chengwei Environment, which collects the leftovers from about 2,000 restaurants in the city of Chengdu. Once the maggots get their fill, the farm sells them (both live and dried) as feed for chicken, fish and turtles. Maggot poop is also sold as agricultural fertilizer.

"The maggots make it possible to recover proteins and fat still present in waste, then return the nutrients into the human food cycle through the livestock," writes Ehret. Because of this, black fly farms have popped up around China in the last several years. There is even a cottage industry of home and small-scale farmers using black soldier fly larva to compost food and produce feed for animals.

In the United States, however, there are currently restrictions on commercial operations feeding animals insects, though many other nations including Canada allow the practice. The European Union will begin allowing insect protein in fish farms beginning in July.

Feeding maggots and other insects to livestock is the future of agriculture, Tarique Arsiwalla, chair of the International Platform of Insects for Food tells Rebecca Kesby at the BBC. “Like in nature, insects are consumed by a lot of animals. For example, many bird species and chickens, and many fish species like trout and young salmon, consume insects in the wild,” he says. “It’s a very natural thing to use insects as animal feed.”

Arsiwalla says some caution needs to be taken with regard to what is fed to the insects themselves, limiting their food to leftover vegetables and fruits rather than manure or other slaughterhouse waste products. But, he says, the use of insect protein solves two big problems in the world: food waste and protein shortage.

Though these tiny crawlers may make you squirm, they just may be a solution to global food waste woes.

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