Mealworms like these, raised by Fred Rhyme of Rainbow Mealworms and Crickets… (Luis Sinco / Los Angeles…)
Do you want to fight global warming? Do you like eating worms?
If so, two scientists at Wageningen University in the Netherlands have an idea for you: Start substituting mealworms for the conventional animal proteins in your diet such as chicken, beef and dairy products.
Writing in the journal PLoS ONE on Wednesday, Dennis Oonincx and Imke de Boer suggested that shifting global diets away from the usual livestock -- the cultivation of which use 70% of agricultural land and is responsible for 15% of greenhouse gas emissions from human activity -- and toward "lower impact animal species" might help.
One of these species, they wrote, could be mealworms, a.k.a. beetle larvae.
This paper attempts to assess total environmental impact in the “production chain” for two species, mealworms (Tenebrio molitor) and super worms (Zophobas morio), grown at a commercial mealworm producer in the Netherlands. It then compares that impact to that of conventional sources like milk, chicken, pork and beef.
The researchers analyzed three indicators of environmental impact: a metric called global warming potential, which takes greenhouse gas emissions into account; fossil energy use; and land use. They had to consider every detail of how mealworms are farmed, including the larvae’s diet — fresh carrots and a “mixed grain feed.” They assessed the environmental impact of the cardboard egg cartons employed in the production process. They counted how much energy was needed to keep the mealworm housed at just the right temperature, as well.
Crunching the data, Oonincx and de Boer determined that global warming potential of producing one kilogram of worms was 2.7 kilograms of CO2 equivalents — significantly lower than milk, chicken, pork and especially beef. Land use, too, was very low compared with the more traditional fare.
Only when it came to energy use did the mealworms not perform quite so well. It takes more energy per kilogram of edible protein to produce mealworms than milk or chicken, and a similar amount to produce pork.
Beef still outdoes worms on energy use, though — and the co-authors also noted that there may be ways for mealworm farmers to reduce their energy use in the future. One possibility, they wrote, is that the larger larvae actually produce their own metabolic heat, which might be somehow harnessed to warm their smaller brethren.
“This study clearly shows that mealworm should be considered as a more sustainable alternative to milk, chicken, pork and beef,” the co-authors concluded.
Of course, there’s one major roadblock in the way: persuading people to chow down on the critters. In the Far East, some do eat mealworms, but in the U.S., they’re primarily doomed to an ignoble end as fish bait and animal feed.
A few intrepid chefs are working to elevate the cuisine, though. At www.insectsarefood.com, one can learn how to make mealworm French fries and banana worm bread. Recipes for mealworm cookies and hot mealworm appetizers are available. This website and this website also offer tips on mealworm cuisine.
For more on eating insects, read this Los Angeles Times post about one ice cream parlor’s effort to popularize a frozen treat made from cicadas.