Pantry Pests
 
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Where do they come from?
Modern food processing and packaging methods virtually preclude the 
possibility of insect infestation at the plant level. When merchandise is 
shopped from a plant, it may go through several channels of distribution before 
it reaches its final destination. Sometimes, goods may be exposed to infestation 
in transit or storage and the result will not be known until it is used by the 
customer.
Infestation can also 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:
- Locate source of infestation. Check seldom-used packages of cereal, flour, 
raisins and spices. Check dry dog and cat food and bird seed. 
 - Wrap heavily infested food in heavy plastic bag and immediately dispose of 
it away from all other foods. 
 - 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. 
 - Store insect-free foods in tightly closed glass, metal or heavy plastic 
containers. 
 - Periodically clean pantry and cupboard shelves, particularly cracks, 
crevices and spaces under shelves. A vacuum cleaner works best. 
 - The use of insecticides has no effect on insects within food packages. 
 
Follow these steps to prevent future infestations:
- Avoid long storage periods by purchasing susceptible or seldom used foods in 
small quantities. 
 - At time of purchase, examine foods such as cornmeal, coarse cereals and 
macaroni to be sure they are insect free. 
 - Store susceptible foods in insect-proof containers. 
 - Heat-treat or cold-treat dried foods that you store for more than 60 days. 
 - Check dry dog and cat food and bird seed often for insects.