I can’t say for sure that there are no cockroach parts in your ground coffee, but there’s no documented evidence of widespread contamination. It’s most likely an urban myth.
In any case, the insects are packed full of nutrients, including calcium, magnesium and iron.
The US Food and Drug Administration (FDA) permits low levels of natural contaminants, including insect parts, in foods.
An FDA handbook also tells manufacturers to ‘take action’ if, on average, 10 per cent or more of green coffee beans are “insect-infested or insect-damaged.” The beans should be easy to spot and removed before coffee roasting.
But cockroaches aren’t really a problem for coffee growers. They’re far more worried about the coffee berry borer beetle (Hypothenemus hampei), which causes widespread destruction.
The females bore into coffee berries and lay their eggs in the seeds – the beans. When the larvae hatch, they devour the beans.
The borer beetle is the only insect that can feed solely on coffee beans without being poisoned by caffeine, thanks to detoxifying bacteria in its guts.
An FDA document calmly states that “larvae, pupae, adults and debris consisting of excreta and cast skins may be found in coffee”.
Another common pest is the coffee bean weevil, which goes for stored beans in warm, damp regions. The beetles and weevils both cause untold damage inside and on the surface of coffee beans.
An FDA guidance document gives tips for ‘reconditioning’ infested or damaged beans. Insects outside the beans can simply be sifted out or blown away before the beans are processed, it says.
If you’re feeling queasy, the best solution would be to buy whole coffee beans and inspect them before grinding them yourself.
If you’re still worried about cockroaches, keep an eye out for them in the warm, moist, dark environment of your coffee machine. As one pest control website says, “if you find a cockroach crawling under or near your coffee maker, chances are there are more of them”.
This article is an answer to the question (asked by Ally Rundell, Stroud) 'Is it true there are ground-up cockroaches in packets of pre-ground coffee?'
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