Insect Fragments in Food

by Food and Drug Administration (FDA)

While reaching over a microscope for one of several scientific handbooks, Richard Trauba, a food specialist in the Food and Drug Administration's Minneapolis district office, says he likes to find antennae because they make his job of identifying insect fragments found in food so much easier.

"Antennae can be very distinguishable," he says. "If you can find the antenna, you can usually nail down the type of common storage insect."

Opening the book and pointing to a page of stalk-like stems, some resembling cattails, Trauba says: "Look at all the differences. Some look like spearheads, some like scales. It's amazing what comes through.

"Mandibles can also be very distinguishable," Trauba continues. "They can come through the milling process without being broken up."

These very distinguishable parts Trauba extracts from food are small — microscopically so, ranging from one-fourth of a millimeter to 4 or 5 millimeters in length. When you consider a millimeter equals less than four-hundredths of an inch, that's small.

Then, too, extracting insect fragments from foods in the first place takes considerable skill and experience. Trauba's interest is more than academic. Working with microscopic insect fragments obtained from food products, FDA scientists are developing evidence for use in enforcing the relevant sections of the Food, Drug, and Cosmetic Act.

According to this law, food is adulterated "if it consists in whole or in part of any filthy, putrid, or decomposed substance, or if it is otherwise unfit for food or if it has been prepared, packed, or held under insanitary conditions whereby it may have become contaminated with filth."

Taking Action

FDA establishes food defect action levels (DALs) for various food products and various types of insects. For instance, the permissible level of certain insect fragments in 50 grams, or about two cups, of flour is 75 parts. (This is the uppermost level at which fragments pose no health hazard in the product.)

According to Paris Brickey, chief of the microanalytical branch, division of microbiology, Center for Food Safety and Applied Nutrition, Washington, D.C., insect fragments may be unavoidable in foods grown outside, exposed to a certain amount of insect contamination.

Brickey says that the amount of insect fragments permitted by the DALs is not only harmless, but "unavoidable to a certain degree. If weevils attack wheat in the field and breed in the kernels, they aren't always removed when the wheat is cleaned, so they get ground up into the product. That's unavoidable."

But there are times when a product is considered contaminated even if the number of insect fragments it contains falls below the DAL. "Certain fragments come from what we classify as filth insects — such as certain types of flies," Brickey explains. "They inhabit filthy areas, often feeding on garbage. Some feed on sores and cuts. They can carry microorganisms. We're not held by defect action levels with these. We'll take action."

When there's an unsanitary practice involved, "we look at it on a case-by-case basis without reference to the numbers," says Brickey. In such cases, FDA scientists evaluate the type of insects as well as the size of the insect fragments.

"In a milled product, this may indicate whether the insects were of post-milling or pre-milling origin. If they were in the wheat before it was milled and were ground up with the flour, that's one thing. If they got into the flour after it was milled, there was probably an unsanitary condition," says Brickey.

The alternative to permissible insect fragment levels, according to Brickey, would be "food so expensive nobody could afford it."

Big Role for L.A.

Trauba estimates that each of FDA's 18 field laboratories has four scientists who regularly extract and identify insect fragments. He readily concedes a first place to the Los Angeles FDA district office, which has nine entomologists (insect specialists) on its staff.

"Los Angeles has a huge collection of fragment slides. One person works on the slide collection full time, going out to zoos collecting new specimens and things like that. They have some strange stuff out there," Trauba says.

Los Angeles' premier position didn't just happen. It's the main port of entry for foods imported from Asia, which frequently aren't processed, packaged and shipped according to U.S. criteria.

Alan Olsen, supervisory entomologist in the L.A. district office, makes it clear that it takes much more than college courses to prepare FDA scientists to find insect fragments in food. Most of these skills are acquired on the job.

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.