If food is infested with weevil, it may be treated in one of several ways.
- Adult insects can be destroyed by placing the food in a freezer at or below 15oF for 3 days. This may not kill all the larvae and eggs so repeat this process after a month. All insects, eggs, and larvae will be killed if frozen at 10oF for 3 days.
- Insects can also be destroyed by heat. Heat grain, layered 3/4-inch deep, on a pan in an oven at 150oF for 20 minutes. Higher temperatures and longer periods of time will reduce germination and, perhaps, handling quality of subsequent flour milled from the grain.
- Put the food in a clean plastic bucket with an airtight lid and treat with dry ice. Dry ice will sublimate to carbon dioxide. Concentrations above 3% are adequate to kill weevil in the closed bucket.
- Put the food in a foil bag lined bucket. Add the appropriate number of oxygen absorbers and seal the foil bag before putting the lid on the bucket.
- Dry pack the food in heavy foil pouches, PETE bottles, or canning jars using oxygen absorbers.
Note: Bay leaf will not kill insects. It only repels them. Diatomaceous earth is not effective in killing most insects found in long-term storage foods. It is most effective against soft-bodied insects or creatures such as slugs and snails.