Cockroaches – the six-legged workers combating food waste
Thursday, 02 May, 2019

Currently, Chinese cities have a 25% share of the world’s municipal solid waste, where the majority of this waste constitutes organic waste. The Chinese Academy of Science and the World Wild Fund states that restaurants and schools are wasting about 33 % of the food they serve. China is using multiple strategies to deal with the issue: municipal landfills, incineration plants where the waste is burned and transformed into electricity (although this is facing difficulties due to moisture content), feeding leftovers to animals (but due to the risk of spreading pathogenic microorganisms, several Chinese municipalities banned this century-old practice) and transforming food in an anaerobic digestion process, thus producing biogas (but this is heavily underrepresented as practice). However, due to the large amounts of waste, China is looking to use a less traditional strategy in the form of cockroaches, an idea that has been piloted in the city of Jinan, inhabited by 9 million people. This “small” (at least in Chinese terms) city is contributing to the country’s waste problem with 6,000 tons of solid waste each day, and about 50-70 % of this is food waste.

To help divert this staggering amount of food waste from landfills, 2 billion cockroaches are housed in a gigantic warehouse where they are kept in a farm-like enclosure and fed food waste. They are part of the waste recycling cycle where waste is delivered to a warehouse after being collected from restaurants. In the warehouse, there is a separation of plastic, glass, and metals from food waste. The food waste is then mushed in a blender and transported to the cockroach farm where they feed on the mush. The final step is the collection of dead cockroaches that are transformed into powder substances and used as animal feed additives. Although they seem high in numbers, they only consume around 100 tons of food waste/day (totaling 1.6 % of total waste in Jinan). To further read about the 46 pilot waste-sorting cities mandated by the Chinese Ministry of Housing and Rural Development as well as with this approach, read “From Farm to Table to Landfills? Seeking Solutions to China’s Food Waste Dilemma”.