Infestation can occur right in the home. Sometimes insects infesting other foods in the cupboard come from unsuspected sources. Food products that are left undisturbed on shelves for 5 to 8 weeks are particularly susceptible to pests, especially in warm, humid weather.
There are many types of insects that attack foods. Some in the larva or adult stage can bore their way into a tightly sealed package. Entrance holes are normally small and difficult to see. Products packaged in glass containers are less likely to become infested. The insects can, however, follow a path up through the screw-on guides under the jar lid and make their way to the top. If this happens, the insect may be discovered between the seal and cap, or possibly in the product itself.
Controlling and Preventing
Follow these steps when food is infested:
1. Locate source of infestation. Check seldom-used packages of cereal, flour, raisins and spices. Check dry dog and cat food and bird seed.
2. Wrap heavily infested food in heavy plastic bag and immediately dispose of it away from all other foods.
3. Heat or freeze susceptible foods after you have had them for 60 days, even if they do not appear infested. Cold treat packaged foods such as cake mixes and spices in their original containers. Expose them to 0 degrees F. or lower temperatures for 3 days or 7 days for larger packages.
4. Store insect-free foods in tightly closed glass, metal or heavy plastic containers.
5. Periodically clean pantry and cupboard shelves, particularly cracks, crevices and spaces under shelves. A vacuum cleaner works best.
6. The use of insecticides has no effect on insects within food packages.
Follow these steps to prevent future infestations:
1. Avoid long storage periods by purchasing susceptible or seldom used foods in small quantities.
2. At time of purchase, examine foods such as cornmeal, coarse cereals and macaroni to be sure they are insect free.
3. Store susceptible foods in insect-proof containers.
4. Heat-treat or cold-treat dried foods that you store for more than 60 days.
5. Check dry dog and cat food and bird seed often for insects.
Excerpt provided by Palm Beach County Cooperative Extension Service