Flour Beetles Aren’t Just in Flour!

By Chris Williams on February 17, 2011.

Q. I opened a new bag of flour yesterday to make cookies and found tiny, wormlike things in the flour bag! They totally grossed me out! What are they and how did they get in an unopened bag?

flour-beetleA. Sounds like you’ve discovered one of our many insect pests that feed in stored food products. You’re most likely dealing with flour beetles. The flour beetle larvae that you saw spend all of their time burrowing and feeding in the food product. The adult beetles that eventually emerge from the flour are very small (but still visible), and dark brown. They are usually found on the outside of infested food packages. These adult beetles secrete chemicals that give infested food a pinkish-grey tint and a characteristic bitter taste and musty smell. The flour may have been infested with beetles at almost any stage from storage to production to packaging to shipment. But the bad news is that the beetles could have come from other products on your own kitchen shelves.

Flour beetles can squeeze into all but the tightest packages, so an infestation in one food package can move quickly into products stored nearby. Flour beetles don’t just feed on flour. They can survive on a wide range of food products – from cornmeal, crackers, cake mix, and cereal, to chocolate, beans, spices, and many more things in between. Unfortunately, that means you will have to check most of the items on your kitchen shelves for beetle larvae. Here’s a hint though; most of the time, the beetle infestation begins in food items that have been on your shelf the longest, or in items that have been overlooked on the back of a shelf. Check first packages that are old, out-of-date, damaged, or damp. And yes, you will have to check or discard everything because you can find them even in unopened packages. If you find only one or two infested products, you can simply discard them (and any other foods that you suspect to be infested). Wash down all shelves and transfer stored foods that are in cardboard boxes or plastic bags to sealed plastic or glass containers. If you find instead that the beetles have taken over your kitchen, you probably need the help of a pest control professional! Call Colonial. We can treat the cracks and crevices around your shelves where beetles may be hiding and can provide you with the peace of mind that comes with a pest-free kitchen.

Look for more information about flour beetles under Stored Product Pests in our website’s Pest Library.



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