Killing bugs with cornstarch
Who says oil and water don’t mix? They do if you add cornstarch.
The USDA’s National Center for Agricultural Utilization Research is working on the process of converting cornstarch and other biobased ingredients into a new class of materials called “amylose inclusion complexes”. They may someday have endless uses – and increase the value of corn.
Bob Behle is a research entomologist working on the project. He says in one study, the material creates a protective film which shows promise for keeping biopesticides on a plant longer.
"Wash off by rain is always an issue. So, my interest was that this inclusion complex could be used as a formulation ingredient to treat a plant. The material would stick to it and hold my beneficial microbes on the plant in the case of rain," says Behle.
Another possible use for the cornstarch emulsion – mosquito control. There are some plant-based essential oils that are toxic to mosquito larvae in the water. The problem is these essential oils don’t like to mix with water. Behle says they found a way.
"By using the amylose inclusion complex we were able to create very stable emulsions in particle sizes that the mosquitoes would feed on in the water column," he says. "And so, as the mosquitoes are feeding, they’re actually taking up the essential oil which would then be detrimental to them."
Cornstarch can also be used in formulations to put the kibosh on wood-damaging termites and rot-causing fungi, including species that cause stored potatoes to go bad.